The Biden administration offered new details this morning about the big, virtual climate summit Thursday and Friday and signaled they expect new emissions reduction and climate finance commitments from multiple countries.

Driving the news: The administration said 40 heads of state would attend, including Russian President Vladimir Putin and President Jair Bolsonaro of Brazil.

• They unveiled a lineup that also includes high-profile names, such as Pope Francis, Bill Gates, the heads of NATO and the World Bank, corporate executives and more.

Why it matters: The White House is trying to reassert U.S. leadership on the climate issue and encourage other countries to make commitments to slash emissions before 2030.

The intrigue: On a call with reporters this morning, officials laid out the summit agenda, but did not say what additional commitments the U.S. will be making on the emissions or climate finance front.

• However, it is widely expected the U.S. will commit to reducing emissions by at least 50% below 2005 levels by 2030, which would put the country near the top of the pack when it comes to emissions targets.

What they're saying: "We expect action at this meeting. We're looking for people to make announcements to raise their ambition to indicate next steps that they intend to be taking to help solve the climate problem and to work collectively to do so," a senior administration official told reporters.

• The administration is also looking to use the summit to showcase its all of government approach to climate — the event will include not only the heads of environmental agencies but also officials like the secretary of defense and the director of national intelligence.

The big picture: The summit comes just after the European Union agreed to a provisional deal overnight on sweeping climate legislation that aims to slash the bloc's net greenhouse gas emissions by 55% compared to 1990 levels by 2030.

Quick take: Biden administration officials can use the deal to show that other countries are acting as President Biden presses Congress for huge new investments and unveils a non-binding target to steeply cut U.S. emissions this decade.

• "Our political commitment to becoming the first climate neutral continent by 2050 is now also a legal commitment," European Commission President Ursula von der Leyen said in a statement.
• In addition, China, the world's largest emitter, announced that President Xi Jinping would attend the virtual summit despite deep tensions with the U.S.
• Separately, the U.K. also announced tougher emissions goals this week, targeting a 78% cut by 2035 compared to 1990 levels.

What we're watching: All eyes are on other countries — notably Japan and Canada — to see if they unveil new targets, and other nations' moves made to date are not necessarily because of the U.S. return to the world stage.

• The U.S. goes into the summit with a credibility gap after former President Donald Trump withdrew from the Paris Agreement. Biden moved to rejoin on his first day in office.

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