Biden calls out Xi and Putin for skipping climate summit despite China and Russia being among world's biggest polluters

• Biden chided Xi and Putin for skipping the UN climate summit.
• China is the world's top greenhouse gas emitter, followed by the US.

President Joe Biden on Tuesday criticized Chinese leader Xi Jinping and Russian President Vladimir Putin for skipping the United Nations climate change conference in Glasgow as well as the recent Group of 20 (G20) summit in Rome, questioning their commitment to fight climate change as other world leaders have sought consensus.

Biden during a news conference at the Glasgow summit, known as COP26, went after China and Russia for what he said was lack of action on some of the world's most pressing environmental challenges. Though Biden appeared in person, both Xi and Putin were physically absent from the summit. Xi submitted a written statement for COP26, while Putin appeared in a pre-recorded video.

"By showing up, we've had a profound impact on the way I think the rest of the world is looking at the US and its leadership role. I think it's been a big mistake, quite frankly, for China not showing up," the president said emphatically.

"The rest of the world is going to look to China and ask what value added are they providing. They've lost an ability to influence around the world and all the people here at COP, the same way I would argue with regard to Russia," he added.

When Biden was later asked how he would get skeptical US lawmakers on board for cutting carbon emissions when countries like China and India have not yet done so, the president was blunt in assessing the importance of his efforts.

"Because we want to be able to breathe and we want to be able to lead the world," he said. "I mean this sincerely. The fact that China is trying to assert, understandably, a new role in the world as a world leader. Not showing up? Come on. The single most important thing that's caught the attention of the world is climate."

"Everywhere, from Iceland to Australia, it's a gigantic issue. They walked away. How do you do that and claim to be able to have a leadership mantle? Same with Putin and Russia. His tundra is burning ... literally, the tundra is burning. He has serious climate problems, and he is mum on the willingness to do anything," he added.

While in Rome last week, Biden also chastised China and Russia for their lack of commitments on climate matters.

"Russia and … China basically didn't show up in terms of any commitments to deal with climate. And there's a reason why people should be disappointed in that. I found it disappointing myself," Biden said a press conference at the conclusion of the earlier summit.

The world's leading scientists have warned for years that countries need to rapidly curb greenhouse gas emissions at a drastic rate in order to avoid climate catastrophe.

The US and China are the globe's top greenhouse gas emitters.

China accounts for roughly 26% of the world's greenhouse gas emissions, per the Center for Climate and Energy Solutions, exceeding all other developed countries combined. Meanwhile, the US is responsible for roughly 13% of global emissions and Russia accounts for about 5.6%.

In this context, Biden also took aim at his Russian and Chinese counterparts in comments at a press conference in Rome following the G20. "Russia and … China basically didn't show up in terms of any commitments to deal with climate. And there's a reason why people should be disappointed in that. I found it disappointing myself," Biden said.

Biden on the campaign trail vowed to place combatting climate change at the top of his agenda. On his first day in office, Biden rejoined the Paris climate accord - a landmark pact between nearly 200 countries to reduce greenhouse gas emissions.

On the domestic front, Biden has sought to address climate change via massive spending proposals that have faced stiff opposition from Republicans and moderate Democrats. Biden last week introduced a $1.85 trillion spending package to expand the nation's social safety net and combat climate change, after previously pushing for a far more expansive $3.5 trillion package.

The president's criticism of Russia and China this week came amid historic tensions between the US and the two major powers. Biden has made challenging both countries a top foreign policy priority, frequently going after Xi and Putin over their anti-democratic, authoritarian policies.

Some experts have described the rising animosity between the Washington and Beijing as a new Cold War, though others contend this is a hyperbolic characterization - particularly given the interconnected nature of the US and Chinese economies.

Biden, who is expected to hold a virtual summit with Xi before the year's end, on Tuesday told reporters he's not concerned that the US and China are on the verge of violent conflict despite the tensions.

"Am I worried about an armed conflict or something happening accidentally with China? No I'm not," Biden told reporters. "This is competition. It does not have to be conflict."

The president added that he's underscored to Xi that he expects the Chinese leader to "play by the rules of the road."

"I'm not looking for, I don't anticipate there will be a need for physical conflict, but you know, as you've heard me say this before, my dad had an expression, 'The only conflict worse than one that's intended, is one that's unintended," Biden added.