Governor Newsom says he will visit Communist China in October to discuss climate change, elevating the governor’s status as a representative of his party at a time when some Democrats are seeking an alternative to President Biden.

At an event for Politico at the California Museum at Sacramento Tuesday, Mr. Newsom said he was going to China due to a breakdown in relations at the national level and because of an “absence of any other leadership.”

“The imperative of maintaining a relationship on climate with China is about the fate and future of this planet,” Mr. Newsom said. “It’s too important; it’s another example where California needs to lead.”

Mr. Newsom clarified that he had coordinated his trip with Mr. Biden, and his administration and he hoped to continue a tradition established by previous governors, such as Arnold Schwarzenegger and Jerry Brown, in acting as delegates for America in its climate relations with China.

Slated to be the first such trip since 2019, the visit will address pre-existing deals on reducing air pollution, electric vehicles, and building out non-fossil fuel energy sources. It comes months after Governor DeSantis visited Japan, South Korea, Israel, and the United Kingdom.

Mr. DeSantis’s trip was billed as a trade mission to demonstrate “Florida’s position as a world economic leader,” but was largely seen as a way to bolster his foreign policy experience ahead of a presidential campaign.

Likewise, Mr. Newsom’s presidential ambitions will loom large over his visit to China, as Democratic voters and some within the party hope that someone other than Mr. Biden will emerge as the nominee for the Democratic Party in 2024.

In a column Tuesday, a pillar of the Democratic establishment, David Ignatius of the Washington Post, said Mr. Biden “should not run again in 2024.”

“I don’t think Biden and Vice President Harris should run for reelection. It’s painful to say that, given my admiration for much of what they have accomplished,” Mr. Ignatius wrote. “But if he and [Vice President] Harris campaign together in 2024, I think Biden risks undoing his greatest achievement — which was stopping [President] Trump.”

While others, like the Guardian’s Sidney Blumenthal in her Wednesday column, argue that Democrats “need to realize there is no alternative to Biden,” it’s clear that Mr. Newsom is positioning himself as the chief alternative to Mr. Biden other than Vice President Harris.

With Mr. Newsom’s propensity to pick fights with Republicans like Mr. DeSantis — with whom he is theoretically supposed to debate sometime this fall — and their surrogates, like Fox News’s Sean Hannity, he’s raised his national profile as a Democrat in recent years.

Mr. Newsom, though, has made it clear that he is throwing his weight behind Mr. Biden in 2024, barring unforeseen circumstances around the president’s health, even as he builds his own national network of donors and supporters.

“The train has left the station,” Mr. Newsom told the New York Times earlier this month. “We’re all in. Stop talking. He’s not going anywhere. It’s time for all of us to get on the train and buck up.”

Mr. Newsom is also not the only elected official making a trip to China in the near future. Majority Leader Schumer announced on Tuesday that he would lead a bipartisan congressional delegation to China, Japan, and South Korea.

Mr. Schumer will be the Democratic leader on the trip, and Senator Crapo, a Republican of Idaho, will be the chief Republican. Although the date for the trip is not public, Punchbowl News has reported that it could happen as early as October.