Disputes over commitments to tackle climate change are the latest flashpoint in tensions between the U.S. and China.

Biden, in recent days, has rebuked China, saying President Xi Jinping’s decision to skip a United Nations (U.N.) climate summit was a “big mistake” because it would diminish Beijing’s influence. China subsequently hit back at the U.S. over the criticism.

The sparks show that even in issues that require international cooperation such as climate change, the strained U.S.-China relationship still reverberates.

World leaders and top negotiators are currently gathered in Glasgow, Scotland, where they’ll make climate announcements and work on finishing up the implementation rules for the global Paris agreement.

Biden attended the conference for two days and is sending a large delegation of Cabinet secretaries. While China also has a delegation, Xi opted not to attend.

“The fact that China, 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 gotten the attention of the world is climate, everywhere,” Biden told reporters Tuesday. “It just is a gigantic issue, and they’ve walked away. How do you do that and claim to have any leadership mantel?"

China hit back, with Foreign Ministry spokesman Wang Wenbin saying, “Actions speak louder than words.”

“What we need in order to deal with climate change is concrete action rather than empty words,” he said. “China’s actions in response to climate change are real.”

In going, Biden can attempt to leave a positive impression on the U.S.’s commitment to climate change, while Xi missed an opportunity to directly engage with other world leaders.

During the climate summit, Biden also hosted a session on the Build Back Better World initiative, a global infrastructure plan he launched with other world leaders over the summer that is meant as a climate-friendly alternative to China’s Belt and Road Initiative for developing countries.

Jennifer Turner, director of the Wilson Center's China Environment Forum, said that even though Xi wasn’t there, China is “still in the driver’s seat.”

“The world has to engage with them,” Turner said, noting that China is the world’s largest emitter.

But she added that it could be an opportunity for the Biden administration to “rekindle all of the clean energy relationships” that were hurt under the Trump administration.

And U.S. climate policy can swing wildly depending on who is in power. Morgan Bazilian, a former European Union (EU) representative during U.N. climate change negotiations, told The Hill that this fact made it all the more important for the U.S. to show up.

“Biden had to show up at the COP this year to show that the United States was back at the table,” Bazilian said. “I’m not sure it’s so important for other heads of state to show up unless they have something to communicate.”

However, Charles Kupchan, who served on the National Security Council under the Obama administration, said that the absence of both China and Russia from the Group of 20 (G-20) and COP26 meetings should serve as a warning sign.

“I think that the fact that neither Russia nor China showed up to the G-20 or the COP26 underscores the degree to which we have a problem, and that problem is that global governance today requires cooperation across ideological dividing lines, and we’re not there yet, and whether we get there is an open question,” Kupchan said.

U.S. officials have repeatedly characterized China’s climate actions as insufficient. The country plans to peak its climate-warming emissions by 2030 and achieve net-zero emissions by 2060.

It also announced at a White House virtual meeting earlier this year that it would reduce its coal use starting in 2026 and “strictly limit” its increase in coal use until then.

The 2060 goal is a decade behind the goal of the U.S. and many other developed countries.

The U.N.’s Intergovernmental Panel on Climate Change has said that in order to limit the world’s warming to 1.5 degrees Celsius, the world needs to reach net-zero emissions around 2050.

It has said that limiting warming to this level would help to evade the worst impacts of climate change.

But China has countered that the U.S. had more time to develop, while China is still developing and therefore deserves more time to wean itself off fossil fuels.

A group of countries that includes China recently put out a statement saying that a global push for net-zero by 2050 would exacerbate inequality.

Meanwhile, the U.S. and EU recently also put China at a trade disadvantage by taking aim at “dirty” steel.

They announced a partnership in which they plan to negotiate an arrangement to address “carbon intensity and global overcapacity” of steel and aluminum products.

Turner said that the move would be “shutting down” China in the steel trade.

And it was seen by some politicians as a China-related issue as well, with Sen. Sherrod Brown (D-Ohio) calling the deal in a statement an “important first step in addressing Chinese steel overcapacity and dumping that has cost Ohio jobs.”

Biden has staked out a broader foreign policy strategy toward China that involves managing and succeeding in competition with China but avoiding conflict.

Still, tensions between the U.S. and China have flared on a variety of fronts, including Chinese military activity near Taiwan. At times, Biden’s firm line on China over human rights abuses and other practices has complicated his administration’s climate efforts. Earlier this year, the Biden administration banned imports of solar material from a Chinese company that officials say is engaged in forced labor practices.

Biden is expected to meet virtually with Xi sometime before the end of the year for his first bilateral engagement with his Chinese counterpart since taking office.

The administration maintains that it can both confront China on areas of disagreement or concern and find ways to work with Beijing on areas of mutual concern.

“Precisely because we live in a world that is so globalized and interdependent, we’re going to have to learn how to compete where we need to and cooperate where we have to, and that’s going to require compartmentalization,” Kupchan said.

“We will disagree on the Chinese on Hong Kong, on Taiwan, on human rights, on trade while at the same time looking for ways to work with them on climate, on global health, on cyber issues, on nuclear proliferation,” he said.