Three months after President Joe Biden pledged America’s return to the fight against global warming at the COP26 summit, youth activists from America and abroad who attended the international gathering are frustrated by the lack of action in Washington.

“It’s a real betrayal of the duty of a representative to serve not only to constituents, but the betterment of humanity,” said Jes Vesconte, an Ohio native and Fulbright scholar now living in Germany.

Vesconte was one of three young climate advocates Spectrum News NY1 checked in with in January, after first interviewing them while on the ground in Scotland in November.

Speaking at the climate summit last fall, Biden promised to go big, pointing to the more than $500 billion in climate investments included in his Build Back Better agenda.

“Will we do what is necessary? Will we seize the enormous opportunity before us?” Biden said at the summit, issuing a challenge to his fellow leaders.

However, Biden’s spending plan — critical to the administration’s pledge to dramatically reduce U.S. carbon emissions — has stalled in the Senate.

Lily Aaron, a high schooler from the Chicago suburbs who is part of the group It’s Our Future, calls the roadblocks in the Senate “depressing,” but said she didn't expect anything less.

“I do not believe we have taken on the leadership position that Biden promised, nor the one that he said in his speech that we hold, especially with the responsibility we do have as the biggest economy in the world and the second biggest emitter,” she said.

The Biden White House points to administrative actions it's taken over the past year, including efforts to create off-shore wind farms.

However, some White House actions have faced criticism, including a major auction of waters in the Gulf of Mexico for oil drilling.

As for that half-trillion dollar climate investment push, as recently as mid-January, Biden expressed some optimism that it could still get done.

“I think it’s clear that we would be able to get support for the $500-plus billion for the energy and environment issues that are there,” he said at a press conference on Jan. 19.

However, whether the spending plan will have a second life in the evenly split Senate, where Democrats cannot afford a single defection, remains to be seen. It is just one of many items on Congress’s to-do list, from funding the government to approving a new Supreme Court justice.

Absent that new spending, some like Vesconte want Biden to be more aggressive in executive actions on climate, testing the limits of his power.

While at the COP26 summit, Vesconte wore an eye-catching shirt, urging Biden to declare a “climate emergency now.”

“He still has time to act on these, right? I'd like for him to prove me wrong,” they said.

Šimon Michalčík, who leads the Czech Republic branch of the environmental group Plant-for-the-Planet, is skeptical. His group aims to plant one trillion trees to buy the world time to reduce emissions.

Michalčík says he would not put too much hope in the federal government, even as the need to act decisively grows.

“It just seems like an easy decision to me. So, I think it should seem like an easy decision to them. If they just read a bit about what's happening,” he said.