The Alliance was formed on June 1, 2017, following the announcement earlier that day by President Donald Trump that he had decided to withdraw the United States from the Paris Agreement.

The Alliance also forms a forum for its members to further develop and strengthen their existing Climate Action Plans, through sharing of information and best practices.

[14][7] The re-election of Donald Trump and the subsequent second withdrawal from the Paris Agreement in 2025 brought the alliance back in the spotlight.

[16] The Alliance was formed on June 1, 2017, following the announcement earlier that day by President Donald Trump that he had decided to withdraw the United States from the Paris Agreement.

The formation of the Alliance was announced by three state governors: Jay Inslee of Washington, Andrew Cuomo of New York, and Jerry Brown of California.

The Alliance is not a legally binding treaty, but a grouping of state governments with similar policies regarding climate change.

[17] The founding press statement was released in three versions on June 1, which all stated that: "New York, California and Washington, representing over one-fifth of U.S.

Gross Domestic Product, are committed to achieving the U.S. goal of reducing emissions 26–28 percent from 2005 levels and meeting or exceeding the targets of the federal Clean Power Plan.

Nearly 70% of Americans, including a majority of people in all 50 states, support the Paris Agreement on climate change.

[2] Election of the Republican governor Joe Lombardo led to Nevada leaving the climate aliance on July 12, 2023.

[1] Following the second inauguration of Donald Trump, he signed an executive order to withdraw from the Paris Agreement for a second time.