WASHINGTON - President Joe Biden will announce a set of executive actions aimed at addressing climate change on Wednesday in a visit to the site of a former coal-fired plant in Massachusetts that is playing a role in supporting the state's offshore wind industry.

Democratic lawmakers and environmental groups have been calling for the White House to take aggressive measures on climate change after Democratic Senator Joe Manchin said last week he was not ready to support key climate provisions in Congress, a critical loss in the evenly divided Senate.

In a visit to Somerset, Massachusetts, Biden will stress that climate change is "an existential threat to our nation and to the world" and will make clear that "if Congress is not going to act on this emergency, then he will," said a White House official.

The former coal-fired power plant that Biden will visit is becoming a manufacturing hub for undersea cables that will support Massachusetts’s offshore wind industry, illustrating the switch from fossil fuels to renewable fuels that Biden has been promoting as critical to reducing climate emissions.

While there, he will unveil a set of executive actions that include steps to protect communities facing extreme heat with money from the Federal Emergency Management Agency and the Health and Human Services Department's Low Income Home Energy Assistance Program (LIHEAP).

The official said Biden also will announce additional actions to boost the domestic offshore wind industry.

Biden has been under pressure to declare a climate emergency, which would enable the use of the Defense Production Act to ramp up production of a wide range of renewable energy products and systems. But the president is not expected to take that step on Wednesday.

Biden promised tough action on climate change in his presidential campaign and pledged in international climate negotiations to cut climate pollution by 50% by 2030 and reach 100% clean electricity by 2035.

But his climate agenda has been derailed by several major setbacks, including clinching enough congressional support to pass crucial climate and clean energy measures in a federal budget bill, record-setting gasoline prices, and global energy market disruption caused by Russia's invasion of Ukraine.

A Supreme Court ruling last month limiting the federal government's authority to issue sweeping regulations to reduce carbon emissions from power plants also is undermining Biden's climate plans.

(Reporting by Steve Holland; Editing by Leslie Adler)