Lead: On January 12, 2026 President Trump issued a presidential memorandum directing the United States to withdraw from the UN Framework Convention on Climate Change (UNFCCC), listing the treaty among 65 organizations and bodies targeted as contrary to US interests. The memorandum did not clarify whether a formal written notice to the UN would be submitted, and UN rules require a one-year notice before withdrawal takes legal effect. Several prominent legal scholars, including Harold Hongju Koh, say the president lacks unilateral authority to exit a treaty the Senate ratified in 1992. The decision has sparked immediate legal and political debate and prompted warnings of litigation and diplomatic fallout.
Key Takeaways
- The presidential memorandum of January 12, 2026 names the UNFCCC among 65 organizations from which the US will withdraw; it is the first time any country has moved to exit the UNFCCC.
- UNFCCC rules require one year’s written notice for withdrawal, so the United States remains a party until at least January 12, 2027 unless procedures change.
- The UNFCCC was submitted to and unanimously ratified by the US Senate in 1992; experts dispute whether a president can undo a Senate-ratified treaty alone.
- By contrast, the Paris Agreement (2015) was not ratified by the Senate, and the US formally left that pact in January 2025 before rejoining or other action by another administration would follow different procedures.
- Legal authorities are split: some argue presidents have historically asserted unilateral withdrawal power; others invoke a “mirror principle” requiring the same level of congressional input to exit as to enter.
- Scholars predict litigation is likely and say reentry could require significant Senate involvement depending on how courts and future administrations interpret the 1992 ratification.
Background
The UN Framework Convention on Climate Change is the foundational international treaty that established the global climate process, first opened for signature at the 1992 Earth Summit and subsequently ratified by the United States with unanimous Senate approval that year. The Paris Agreement of 2015 sits under the UNFCCC umbrella but, unlike the convention, the United States did not submit Paris to the Senate for ratification; previous administrations treated Paris as an executive agreement rather than a treaty requiring two-thirds Senate consent.
Under the UNFCCC text and related rules, any party wishing to withdraw must give one year’s written notice before withdrawal takes effect. The constitutional question of who can lawfully terminate a treaty the Senate has ratified remains unsettled: the Supreme Court addressed aspects of treaty exit in 1979 during litigation over President Carter’s withdrawal from a diplomatic treaty with China but produced no single controlling rationale. Over decades, several presidents have asserted broad authority to change or leave international commitments, producing a mixed record of executive practice and congressional acquiescence.
Main Event
On January 12, 2026 the White House published a presidential memorandum ordering the withdrawal of the United States from the UNFCCC and a list of 65 organizations and agreements that the administration deemed counter to US interests. The memorandum directed agencies to take all steps to implement the withdrawal as soon as possible but did not state explicitly whether a formal one-year notice would be filed with the UN secretariat. A State Department spokesperson referred questions to the text of the memorandum and to Secretary of State Marco Rubio’s public statement that the administration is exiting multilateral bodies it deems redundant, mismanaged, or inimical to US sovereignty and prosperity.
Senior legal scholars reacted within hours. Harold Hongju Koh, former legal adviser to the State Department and now at Yale, told reporters in qualified terms that in his view the president lacks unilateral authority to terminate a Senate-ratified treaty. Michael Gerrard of Columbia Law noted the factual difference between the UNFCCC and the Paris Agreement: the former was ratified by the Senate in 1992, the latter was not. Rhode Island Senator Sheldon Whitehouse called the move illegal and signaled immediate congressional and legal pushback.
Practically, the UNFCCC remains binding on the US for at least one year if the administration follows the convention’s written-notice requirement; if the administration fails to file notice the legal posture would be more ambiguous and likely invite lawsuits. Environmental groups, states, and cities have already indicated they will consider litigation to block or delay the withdrawal, and several foreign governments have said the decision undermines US credibility on long-term climate cooperation.
Analysis & Implications
The central legal dispute revolves around constitutional structure and precedent. The Constitution provides that treaties are made with the advice and consent of the Senate, but it does not explicitly state how treaties are terminated. Some scholars, invoking a mirror principle, argue that the same collective Senate role required to ratify should be required to withdraw; others point to decades of executive practice asserting withdrawal power without explicit congressional authorization. That split leaves the question both legally complex and politically charged.
If courts accept the executive’s unilateral withdrawal, the decision would strengthen future presidents’ leverage to dissolve international commitments, altering the balance of treaty permanence and potentially weakening the Senate’s treaty role. Conversely, if courts require Senate involvement or congressional authorization to withdraw, the decision could be stayed or reversed pending congressional action, reinforcing legislative checks on executive foreign policy moves.
Beyond constitutional law, the practical implications are significant for climate diplomacy. Allies and partners view the US exit as a sign of unreliability on long-term commitments, which could slow cooperative investments, carbon markets, and joint research initiatives. Domestically, federal retreats from multilateral frameworks shift more responsibility to states, cities, corporations, and subnational coalitions, but these actors cannot substitute fully for coordinated national policy and international bargaining power.
Comparison & Data
| Agreement | US Senate Ratification? | Year | Withdrawal Rule |
|---|---|---|---|
| UNFCCC | Yes (unanimous) | 1992 | One year written notice |
| Paris Agreement | No (executive instrument) | 2015 | One year written notice under Paris text; no Senate ratification required historically |
The table shows the key legal distinction: UNFCCC was formally ratified by the Senate in 1992 whereas the Paris Agreement was implemented without that step. That difference is at the heart of expert disagreement about whether President Trump may withdraw unilaterally or whether Senate action is required to end the US’s treaty status.
Reactions & Quotes
Public and official reactions ranged from legal caution to outright condemnation, reflecting the polarized domestic context and global concern.
In my legal opinion, the president does not have the authority to unilaterally terminate a treaty ratified by the Senate.
Harold Hongju Koh, former State Department legal adviser (academic)
Koh’s statement frames the central legal argument that a treaty entered with Senate approval should require comparable congressional input to be revoked.
This administration is exiting institutions and treaties it views as redundant or harmful to US sovereignty and prosperity.
Secretary of State Marco Rubio (administration statement)
Rubio’s remark summarizes the administration’s stated rationale and signals an intent to proceed rapidly, though procedural steps remain unclear.
This withdrawal is not just corrupt, it is illegal.
Senator Sheldon Whitehouse (elected official)
Senator Whitehouse links the legal argument to political critique and indicates likely congressional opposition and oversight action.
Unconfirmed
- Whether the administration has filed or will file a formal one-year written notice with the UN secretariat has not been publicly confirmed as of January 12, 2026.
- It is unconfirmed whether courts will enjoin the administration or how quickly litigation will proceed if filed by states, cities, or NGOs.
- There is no settled legal outcome about whether reentry into the UNFCCC would require a new two-thirds Senate vote; experts disagree and this remains to be judicially or politically resolved.
Bottom Line
The January 12, 2026 memorandum ordering withdrawal from the UNFCCC raises fundamental constitutional and practical questions about who can end a treaty the Senate ratified. The one-year notice requirement means the US remains a party for at least a year if the administration files notice, but the lack of clarity about formal procedures and the strong views of legal experts make litigation and congressional action likely.
Beyond courts, the move damages American credibility in multilateral climate talks and shifts responsibility for climate action to nonfederal actors and foreign partners, complicating coordinated global responses just as climate impacts intensify. The outcome — whether the withdrawal proceeds, is blocked, or is reversed — will shape US climate diplomacy and the constitutional boundaries of executive power for years.