GLASGOW — President Joe Biden joined world leaders Tuesday to emphasize the importance of preserving forests against global warming. He also whipped up ambitions at a U.N. Climate Summit abroad while a coal-state U.S senator threatens Biden’s landmark climate legislation here at home.

Democratic Senator Joe Manchin’s comments that he still doubts Biden’s domestic policy proposal of $1.75 trillion, which includes $555 Billion in provisions to combat climate changes, are unfortunate for the president.

They arrived as Biden and his aides were exhorting, coaxing, and making deals with government heads to accelerate action on climate-wrecking fossil fuel emission reductions at a summit in Glasgow, Scotland, with more than 100 world leaders.

Manchin is a senatorial vote holder. Biden holds the slimmest Democratic majority and Manchin has repeatedly killed key climate proposals. He stated Monday that he was not sure about the legislation’s effect on the economy or federal debt, and was open to voting against it as well.

Biden is determined to show the world that the U.S. is still involved in the global fight against climate change after Donald Trump, the U.S.’s predecessor, pulled it out of the 2015 Paris climate agreement.

Biden stated Monday that the United States should be on a path to reduce its coal, oil, and natural gas pollution by half by 2050. This is what his climate legislation aims to do.

He said, “I know that hasn’t always been the case”, in reference to Trump.

Biden basically bets that Democrats will elect Democrats who have the right combination of policies on climate and economy. There are still questions about his ability to build enough political capital in the United States to fulfill his pledges to world leaders to shift the U.S. towards renewable energy.

Tuesday’s Gubernatorial Elections in Virginia and New Jersey, which Biden won last year in the election — will be the first ballot box test of Americans’ views on his presidency.

Biden was joined by other leaders Tuesday to support safeguarding the forests of the world, which remove large amounts of carbon pollution. The administration, as part of an international effort to stop natural forest loss, intends to allocate up to $9 billion to climate funding for the issue.

Biden stated that forests have the potential to reduce carbon by more than one-third globally.

To promote alternatives to China’s infrastructure financing programs, the president hosted an event along with Ursula von der Leyen, President of European Commission. Biden said that his “Build Back better World” policies were similar to Chinese programs and that he would not allow countries seeking infrastructure funding to be exposed to “debt traps or corruption.”

Biden will host a news conference after discussions on technology and methane. It is crucial that Biden emphasizes several policies that can be reached without congressional buy in, including methane pledges or private partnerships.

His administration decided Tuesday to launch a broad-based plan to reduce methane emission, which is a powerful greenhouse gas that significantly contributes to global warming.

Biden arrived at the summit stating that he wanted to see his legislation passed this week. But Manchin’s new objections could close the window Biden might have to get his initiatives passed. Despite the fact that coal is less competitive in U.S. energy markets, Biden wants to protect his state’s coal industry.

Biden could limit his climate legislation failure to projects that could easily be overturned next U.S. President. This would turn his passionate cries for climate action overseas into wistful talk back home.

Manchin’s statements could indicate that one of the two key Democratic votes in Senate wants to hold off on voting on President Obama’s agenda until it is fully reviewed. House Democrats are continuing to work this week to pass Biden’s $1 trillion infrastructure package. This includes efforts to combat climate change. In the hope of appeasing a diverse, sometimes fractious Democratic caucus, the White House seeks to make both measures law and link them.

Jen Psaki, White House Press Secretary, retorted by stating that the administration was confident that the spending package meets Manchin’s criteria.

Psaki stated that the plan is fully funded, will reduce deficit and bring down costs for housing, health care, childcare and elder care. We remain positive that Senator Manchin will support the plan.”

Biden spoke of the difficulty of leading globally on climate change in a time when there are political divisions within the United States. Biden made a seemingly spontaneous comment Monday about the Trump-era collapse of U.S. climate initiatives.

He said, “I shouldn’t apologize, however, I do apologize for that fact the United States (the last administration) pulled out from the Paris accords, and put us kind of behind the eight ball somewhat,”