Signed with Advice and Consent, Withdrawn Without: Trump’s Unilateral Withdrawal from the UNFCCC

On January 7, 2026, President Trump issued a memorandum entitled Withdrawing the United States from International Organizations, Conventions, and Treaties That Are Contrary to the Interests of the United States, announcing the withdrawal of the United States from sixty-six “entities,”[i] most of which were neither organizations, conventions, nor treaties.[ii]

Among this laundry list of entities deemed “wasteful, ineffective, or harmful,”[iii] the fifty-seventh entry sticks out: the UN Framework Convention on Climate Change, commonly known as the UNFCCC.[iv]

The UNFCCC is a consequential international climate agreement that has governed global climate diplomacy for more than three decades.[v] Aimed at stabilizing greenhouse gas concentrations in the atmosphere, the UNFCCC is the “parent treaty” to agreements that have found their way into the everyday conversation, including the Kyoto Protocol and the Paris Climate Agreement.[vi] Since its adoption in 1992, 198 countries have ratified the treaty.[vii] Once the first industrialized country to join the treaty, the United States now charts a troubling first – becoming the first nation to withdraw from a cornerstone of the international climate framework.[viii] Given the United States’ outsized financial and symbolic role, this withdrawal represents a serious blow.[ix]

Amid profound geopolitical and environmental anxiety, a familiar legal question emerges: not whether the President should withdraw from the UNFCCC, but whether the President can.  And, if so, what such a unilateral action means for future presidents who may seek to reenter the Convention?

Article II of the Constitution grants the President the power, “by and with Advice and Consent of the Senate, to make Treaties, provided two-thirds of the Senators present concur.”[x] That is precisely how the United States became a party to the UNFCCC in 1992, when President George H. W.  Bush submitted the treaty to the Senate, which consented by a unanimous 92-0 vote.[xi]

What the Constitution does not address, however, is whether the President may unilaterally withdraw from a treaty entered into with the Senate’s advice and consent.[xii] On that question, legal scholars take different views,[xiii] and the Supreme Court has yet to resolve it.[xiv]

Some scholars believe the President can. Rather than pointing to explicit legal authority, these legal scholars look to historical practice and custom. Congress has historically acquiesced to unilateral executive withdrawals from international commitments for which the Senate has provided its advice and consent, including the Ford Administration’s withdrawal from the International Labour Organization and the Reagan Administration’s withdrawal from the United Nations Educational, Scientific and Cultural Organization (“UNESCO”).[xv]

Other legal scholars believe the President cannot. Former legal advisor of the State Department, Harold Hongju Koh, has argued that past congressional silence should not be dispositive; instead, withdrawal should require the same level of congressional participation as entry, the so-called “mirror principle.”[xvi]

Legal scholars are similarly divided over whether a future president could reenter the UNFCCC without renewed Senate approval. Some contend that reentry would be permissible, again pointing to International Labour Organization and UNESCO, which were rejoined by the Carter and Bush administrations, respectively, following unilateral withdrawal.[xvii] Others maintain reentry would require two-thirds Senate vote – a daunting prospect in today’s world of hyper-partisanship.[xviii]

But the implications of this constitutional debate extend far beyond the borders of the United States. Because the UNFCCC enjoys near universal participation, with nearly every country in the world as a party, the United States’ withdrawal carries serious consequences for international cooperation.[xix] The Convention, and thus global climate action, depends on coordinated participation through annual negotiations that structure climate policy and provide a forum for collective decision-making. [xx]

As practice has developed over time, treaty commitments have increasingly been governed by executive custom rather than an implicit extension of constitutional text.[xxi] Repeated congressional acquiescence has effectively elevated this historical practice into a controlling constitutional norm.[xxii] As a result, treaty participation has become contingent on presidential discretion in practice.[xxiii] This uncertainty weakens U.S. diplomatic credibility and invites instability among foreign partners.[xxiv] Because nearly every other nation remains a member of the UNFCCC, the United States’ custom-driven regime reinforces perceptions of American unreliability and undermines not only the stability of the climate framework, but international cooperation more broadly. [xxv]

In the meantime, the United States confronts a more immediate reality: a President who, shielded by constitutional custom, views the limits of his authority not through international law, the courts, or the Constitution, but through his own morality.[xxvi] And, when withdrawal rests on individual discretion rather than institutional constraint, the resilience of international commitments becomes uncertain.

Alexandra Levine is a staff member of Fordham International Law Journal Volume XLIX.

[i] See The White House, Memorandum on Withdrawing the United States from International Organizations, Conventions, and Treaties That Are Contrary to the Interests of the United States (Jan. 7, 2026), https://www.whitehouse.gov/presidential-actions/2026/01/withdrawing-the-united-states-from-international-organizations-conventions-and-treaties-that-are-contrary-to-the-interests-of-the-united-states/.

[ii] See Jean Galbraith, Retreating from Internationalism: The Announced U.S. Withdrawal from Many International Entities, Verfassungsblog (Jan. 10, 2026), https://verfassungsblog.de/the-announced-u-s-withdrawal-from-many-international-entities/.

[iii] See U.S. Dep’t of State, Statement on Withdrawal from Wasteful, Ineffective, or Harmful International Organizations (Jan. 7, 2026), https://www.state.gov/releases/office-of-the-spokesperson/2026/01/withdrawal-from-wasteful-ineffective-or-harmful-international-organizations.

[iv] See The White House, supra note 1.

[v] See Somini Sengupta, What Is the UNFCCC and Why Is the U.S. Pulling Out?, The New York Times (Jan. 7, 2026), https://www.nytimes.com/2026/01/07/climate/what-is-unfccc-climate-treaty.html.

[vi] See U.N. Framework Convention on Climate Change, About the Secretariat, https://unfccc.int/about-us/about-the-secretariat (last visited Jan. 12, 2026).

[vii] See Sengupta, supra note 5.

[viii] See id.

[ix] See Joe Lo, Legal Experts Say Trump Could Quit Paris Pact – But Leaving UNFCCC Much Harder, Climate Home News (Nov. 4, 2024), https://www.climatechangenews.com/2024/11/04/legal-experts-say-trump-could-quit-paris-pact-but-leaving-unfccc-much-harder/.

[x] U.S. Const. art. II, § 2.

[xi] See Daisy Dunne et al., Q&A: What Trump’s US Exit from UNFCCC and IPCC Could Mean for Climate Action, Carbon Brief (Jan. 9, 2026, 3:19 PM), https://www.carbonbrief.org/qa-what-trumps-us-exit-from-unfccc-and-ipcc-could-mean-for-climate-action/.

[xii] See generally U.S. Const. art. II.

[xiii] See Taylor R. Dalton, Exit Through the White House: Congressional Constraints on Unilateral Presidential Withdrawal from Treaties, 12 Tex. A&M L. Rev. 207, 228 (2024)

[xiv] See Goldwater v. Carter, 444 U.S. 996, 997 (1979).

[xv] See Dunne, supra note 11. The Paris Climate Agreement did not implicate this concern when Trump withdrew because the agreement had not been previously submitted to the Senate. See Dharna Noor, Trump’s Move to Pull US From Key UN Climate Treaty May Be Illegal, Experts Say, The Guardian (Jan. 12, 2026, 7:30 AM), https://www.theguardian.com/us-news/2026/jan/12/trump-un-climate-treaty-unfccc.

[xvi] See Noor, supra note 15.

[xvii] See Dunne, supra note 11.

[xviii] See Sengupta, supra note 5.

[xix] See id.

[xx] Cf. Jillian Goodman, Can Trump Exit a Senate-Approved Treaty? The Constitution Doesn’t Say, Heatmap News (Jan. 10, 2026), https://heatmap.news/climate/unfccc-treaty-withdrawal.

[xxi] See Taylor R. Dalton, Exit Through the White House: Congressional Constraints on Unilateral Presidential Withdrawal from Treaties, 12 Tex. A&M L. Rev. 207, 228 (2024).

[xxii] See id.

[xxiii] Cf. Galbraith, supra note 2.

[xxiv] See id.

[xxv] Cf. Jake Schmidt, Quitting and Rejoining Global Climate Agreements: What’s at Stake for the United States, Natural Resources Defense Council (Jan. 10, 2026), https://www.nrdc.org/bio/jake-schmidt/quitting-and-rejoining-climate-agreement-whats-stake-united-states.

[xxvi] See David E. Sanger et al., Trump Lays Out a Vision of Power Restrained Only by ‘My Own Morality,’ The New York Times (Jan. 10, 2026), https://www.nytimes.com/2026/01/08/us/politics/trump-interview-power-morality.html.

This is a student blog post and in no way represents the views of the Fordham International Law Journal.