President Joe Biden speaks during a news conference at the White House on November 9, 2022.
CNN  — 

President Joe Biden arrives Friday at the UN’s COP27 summit in Egypt with a climate change victory in-hand: a massive US law passed this year that experts have told CNN will go far to help transition the country to renewable energy.

Democrats’ Inflation Reduction Act contained $370 billion for climate and clean energy tax credits and new programs – the largest climate-related investment in the country’s history and a significant statement that the US is back in the clean-energy race.

But that law left out an important thing: international climate finance – funds to help poorer countries adapt to the climate crisis and grow their economies without becoming dependent on fossil fuel.

Last year, Biden pledged to contribute $11.4 billion per year to that fund, something he hoped would go a long way in helping developed nations meet the $100 billion a year they pledged to raise by 2020 and have thus far fallen short on.

Whether Biden can marshal that much funding is unclear; while senators attending COP27 told CNN they expect Congress to pass a government spending bill by the end of this year, it remains to be seen whether Biden’s full international goal will be approved.

“We would like, as Democrats, to get a lot of support for the international Green Fund or other means of providing support to transitioning economies into this bill,” said Sen. Sheldon Whitehouse of Rhode Island. “The obstacle is Republican opposition, and the Republican opposition is driven by the fossil fuel industry.”

Democratic majorities in the US Senate are already razor thin, meaning Republicans will have significant input on appropriations. And all are watching to see whether the balance of power in Congress could change after a competitive midterm election.

“The politics in Washington is always challenging on any appropriations bill,” Sen. Ben Cardin of Maryland told CNN. “I hope the House is controlled by Democrats, but it’s still going to be challenging to make funds available – we recognize that.”

A senior administration official said that while a new budget bill could pass before a new Congress takes control in January, the potentially shifting politics around the midterms puts big question mark how control of Congress could impact US climate finance in the coming years.