On 20 January 2025, President Donald Trump signed an executive order to begin the withdrawal of the United States of America (US) from the World Health Organization (WHO).
At the core of the decision is US criticism of the WHO’s “mishandling” of the COVID-19 pandemic and other global health crises, including its alleged “failure to adopt urgently needed reforms”, its “inability to demonstrate independence” from the political influence of other Member States, especially China, and for the “unfairly onerous” payments demanded from the State, compared to other countries. Notably, for decades the US has been the largest donor to the WHO, supporting it through assessed and voluntary contributions. In the 2022-2023 biennium alone, it provided US$ 1.284 billion, accounting for approximately 20% of WHO’s total budget for the same period (see here).
Already in 2020, President Trump had begun the exit process from the Organization, but the order was later reversed by President Joe Biden on his first day in office, before the one-year notice expired. Now, having returned to power, Trump has revived his previous initiative as one of the first acts of his Second Administration, which makes it more likely that the US will actually leave the WHO this time. The move came as no surprise. Yet, it signaled another piece in the ongoing crisis of multilateralism, largely driven by the US abandonment of several negotiations, agreements, and international organizations. Just to mention a few recent examples, it is worth recalling the US withdrawal from the Paris Agreement, the Trans-Pacific Partnership, and the Human Rights Council, among others, as well as the imposition of sanctions on the International Criminal Court.
At a time when common concerns, such as the spread of infectious diseases, necessitate “reinforced” cooperation to be dealt with (CESCR General Comment No. 25, paras. 77-84), the US disengagement from multilateral institutions risks setting a dangerous precedent for other States, potentially undermining collective efforts to address global health challenges. Against this backdrop, clarifications on the legal basis for withdrawing from the WHO could help provide better context and assess the feasibility of exit policies in the near future.
The Right of Withdrawal under the WHO Constitution
Notably, the WHO constitutive instrument does not contain a withdrawal provision. At the time of negotiations, the precedent of 16 States leaving the League of Nations based on an explicit right to exit in its Covenant brought the drafters of the WHO Constitution to remain silent on the issue, as previously done with the UN Charter (Schermers and Blokker, p. 110 ff). Indeed, according to the founding members, the Organization was to be informed by the principle of universality, and the inclusion of an explicit right to withdraw would have jeopardized adherence to such an approach (Burci and Vignes, p. 28).
As a general rule, according to Art. 56 of the 1969 Vienna Convention on the Law of Treaties (VCLT), a treaty that does not explicitly grant the right to denunciation or withdrawal is not subject to these actions unless the parties intended to allow them, or when such a right may be implied by the nature of the agreement. With particular regard to the WHO Constitution, the intention of the parties to allow withdrawal – under specific circumstances – can be inferred from a declaratory statement unanimously adopted during the 1946 New York Conference (Official Records 2, p. 26). According to the statement, “[a] member is not bound to remain in the Organization, if its rights and obligations as such are changed by an amendment of the constitution in which it has not concurred and which it finds itself unable to accept” (Ibid., pp. 26 and 74). Therefore, the statement seems to acknowledge members’ right to withdraw, but only in the limited case of a substantial amendment to the founding treaty. Beyond this scenario, it should be concluded that contracting parties intended to exclude a general right of withdrawal from the WHO Constitution.
The Legal Basis for US Withdrawal from the WHO Constitution
In 1948, when Congress authorized US membership in the WHO, concerns about the absence of a withdrawal provision in the Constitution of the Organization led the House and Senate to enact a joint resolution explicitly reserving the State a right to revoke membership upon one-year notice (in line with Art. 56(2) of the VCLT) and “provided, however, that the financial obligations of the United States to the Organization shall be met in full for the Organization’s current fiscal year” (Public Law 643, 80th Congress, Section 4; Official Records 13, p. 383). The resolution was eventually attached to the instrument of acceptance as a reservation. On 2 July 1948, in accordance with Art. 20(3) of the VCLT, the World Health Assembly unanimously recognized that the US had validly ratified the WHO’s founding instrument with this reservation (WHA1.76, p. 295).
Given the one-year notice requirement, the exit process is expected to be finalized by January 2026, provided that the US does not retract the notification of withdrawal and pays its contributions in full for the entire fiscal year (Galbraith 2020; Galbraith 2025). Interestingly, the joint resolution adopted by US Congress does not clarify whether the US is required to pay through the year in which it notified its intention to pull out (2025) or the year in which the withdrawal is expected to take effect (2026). Neither is it clear whether the President has the authority to terminate membership without prior approval by Congress (The World Health Organization (WHO): Background and U.S. Withdrawal, p. 2). Both questions carry significant weight as they pertain to the very legitimacy of the US withdrawal and have a direct impact on the functioning of the Organization. Indeed, halting funds can undermine efforts to prevent and control the spread of diseases, increasing the risk of illness and death for people with preventable health conditions such as HIV/AIDS, hepatitis, and tuberculosis (Gostin, Mason Meier and Pace).
While it is beyond the scope of this article to engage in a discussion on US constitutional law (but see Galbraith, pp. 771-772), some scholars have convincingly argued (Woolaver, Helfer, Nesi, and Russo; but see contra Kolb) that, as a general rule, if a withdrawal procedure is in violation of fundamental norms of domestic law (as those provided in the Congress joint resolution), the unilateral act could also be deemed invalid at the international level, applying by analogy Art. 46 of the VCLT. Hence, under international law, the State in question would not cease to be a WHO Member.
The Uncertainties Surrounding Other Members’ Right to Withdraw from the WHO
Despite significant public health concerns surrounding the US decision, other countries have already signaled their intent to follow suit. On 5 February 2025, Argentinian President Javier Milei announced plans to withdraw from the WHO. Similarly, Italian Deputy Prime Minister Matteo Salvini has proposed a law aimed at granting Italy a right to exit the Organization. In Hungary, internal debates have revolved around the possibility of pulling out.
However, only the US has explicitly granted itself the right to withdraw from the Organization by making a reservation to the WHO Constitution. By contrast, the recent statements issued by other States’ leaders appear to lack sufficient grounds for consequential lawful actions. Taking Argentina as an example, the official statement recently issued by President Milei hardly aligns with either Art. 56 of the VCLT or the declaration adopted at the 1946 New York Conference. Indeed, while the comunicado echoes the US order in claiming that the WHO is engaging in international politics rather than adhering to its mandate and goals, this position does not fit within the hypothesis of a situation where a contracting State’s rights and obligations have changed due to an amendment of the Constitution in which the latter “has not concurred and which it finds itself unable to accept”. Nor is there evidence that Argentina has formulated a reservation to the WHO Constitution, granting itself a right to withdraw.
Similar arguments may apply to the situation of Italy and Hungary. Although their internal debates focus on adopting national laws to exit the WHO, whether they enjoy a right to pull out under the law of treaties is questionable.
The unsuitability of their political statements for the purpose of withdrawing appears to be confirmed not only by the mentioned travaux préparatoires of the founding instrument but also by the subsequent practice in the implementation of the WHO Constitution (Greco, pp. 32-33). To date, ten States have attempted to terminate membership in the WHO. The first instance dates back to 1949, when Soviet Russia and the Socialist Republics of Ukraine and Belarus notified their intention to withdraw. Between 1950 and 1951, Bulgaria (Official Records 25, p. 28), Poland (here, p. 324), Romania, Albania, Czechoslovakia, Hungary, and the then Republic of China (Official Records 28, pp. 553-555) also expressed their intent to exit the Organization. Interestingly, most of these States declared that they “no longer consider themselves Members of the World Health Organization” rather than invoking the “right to withdraw”. Only China, Poland, and Romania explicitly referred to such a right.
Since the WHO did not recognize their withdrawal, “[b]ecause the Constitution of the WHO makes no such provision” (Official Records 17, p. 52, Peters, pp. 347-349), those States were merely considered as “inactive members” (WHA9/SC.1/Min/1, p. 13; Official Records 21, p. 52; Bertrand). As a consequence, when the same countries later requested the resumption of their active participation in the Organization, they were only required to pay a fee related to previous years, without the need for a new admission procedure (Official Records 42, pp. 424-425; see also WHA6.6 where the Assembly “welcome[d] the return of China to ‘active participation’”; Official Records 48, pp. 18-19). For instance, the Socialist Republics were mandated to pay 5% of the contributions due for the years of inactivity (Official Records 71, pp. 19 and 153 ff.), and the depository status page for the founding treaty indicates that they joined the WHO in 1948, rather than when their participation was resumed in 1955 (Galbraith, p. 770). Finally, the very fact that the then International Sanitary Regulations, adopted with an opting-out procedure in 1951, were considered binding on the “inactive members” despite no specific arrangements, supports the view that their withdrawal had no effects under international law (Vignes, p. 655).
Conclusion
In conclusion, in the absence of a withdrawal provision in the WHO Constitution, the right to terminate membership is only permissible upon a specific reservation or in response to substantive amendments to the founding treaty (Burci and Vignes, pp. 28-30). Any other initiative expressing the intention to withdraw from the Organization would have no legal effect under international law and would result in the State’s simple inactivity, with the possibility of resuming participation upon payment of outstanding fees.
As for the US, the withdrawal is legally grounded on the reservation to the WHO Constitution, granting the State a right to pull out. This withdrawal could be either permanent or temporary, as it was for UNESCO, where the US withdrew in 1984 over criticism of the Organization’s programs, rejoined in 2003, and left again in 2018.
By contrast, for other WHO Member States, the situation appears far more complex, with no clear legal pathway to exit the Organization. However, empirical evidence shows that international cooperation cannot be sustained through “forced marriages” by merely invoking the boundaries of the law of treaties. Within this context, the WHO’s invitation for the US to engage in dialogue and maintain the partnership with the Organization can be seen as an effort to not only encourage the State to uphold its commitment towards the statutory goal of the “attainment by all peoples of the highest possible level of health”, but also to prevent a chain reaction that could undermine global health governance.