UN says U.S. withdrawal from Paris climate pact takes effect Jan. 27, 2026

The United States’ withdrawal from the Paris climate agreement took effect on Tuesday, January 27, 2026, the United Nations said after receiving the required formal notification a year earlier. The move marks the second time President Donald Trump has taken the U.S. out of the 2015 pact, which underpins global cooperation to limit temperature rise and reduce greenhouse-gas emissions. ([yahoo.com](https://www.yahoo.com/news/us-withdraw-climate-deal-jan-164454005.html?utm_source=openai))

Under the agreement’s withdrawal clause, a party must provide written notice and then wait one year for the exit to become effective. The UN depositary process means the decision has a fixed date of legal effect, regardless of domestic political debate over climate policy. ([congress.gov](https://www.congress.gov/crs-product/R48504?utm_source=openai))

The Paris Agreement commits nearly 200 countries to pursue national climate plans and to strengthen them over time, with a shared goal of keeping warming well below 2°C and pursuing efforts to limit it to 1.5°C. U.S. withdrawal does not end climate action by states, cities, and companies, but it complicates diplomacy and can weaken momentum for coordinated international steps, especially around financing and shared targets. ([congress.gov](https://www.congress.gov/crs-product/R48504?utm_source=openai))

In practical terms, the U.S. exit increases uncertainty for global negotiations as countries prepare future rounds of climate commitments. Other major emitters are expected to continue their own plans, but negotiators now have to account for the absence of the world’s largest historical emitter from the core agreement’s framework. ([kffhealthnews.org](https://kffhealthnews.org/morning-briefing/tuesday-january-27-2026/?utm_source=openai))

The withdrawal is effective as of January 27, 2026, meaning it is now in force internationally. Any future U.S. return would require a new political decision and a formal process to rejoin the accord. ([congress.gov](https://www.congress.gov/crs-product/R48504?utm_source=openai))