President Joe Biden compared Chinese President Xi Jinping to “dictators” during a political fundraiser in California Tuesday night, delivering the unscripted remarks roughly a day after US Secretary of State Antony Blinken said his recent trip had yielded “progress” in repairing the fractured relationship between Washington and Beijing.

“The reason why Xi Jinping got very upset in terms of when I shot that balloon down with two boxcars full of spy equipment in it is he didn’t know it was there. No, I’m serious. That’s what’s a great embarrassment for dictators, when they didn’t know what happened,” Biden told attendees at the fundraiser in the Bay Area, referring to the Chinese spy balloon that the US shot down earlier this year.

The president’s apparently off-message remarks come amid a particularly tense time in US-China relations. Washington’s top diplomat said Monday that the US and China had made “progress” toward bringing relations back on track with both sides agreeing on the need to “stabilize” their bilateral relationship.

CNN has reached out to the White House about the president’s comment.

Biden in his remarks also praised Blinken’s work to repair the relationship by reiterating he “did a good job” and adding that improving the relationship would “take time.” At a second fundraiser Tuesday, Biden told donors that US climate envoy John Kerry would also hopefully be making a trip to China “pretty soon” with a focus on the environment.

Blinken – who is the first US secretary of state to visit Beijing in five years – recently wrapped up two days’ worth of meetings in the Chinese capital with top officials, including Xi, which resulted in no major breakthroughs but agreements from both sides to continue further diplomatic engagements.

“We’re not going to have success on every issue between us on any given day, but in a whole variety of areas, on the terms that we set for this trip, we have made progress and we are moving forward,” Blinken said at news conference in Beijing on Monday.

And Biden for his part told reporters as recently as this weekend that he hopes to meet with Xi over the “next several months.”

The president on Tuesday went into additional detail on some of the ongoing tension between the two superpowers. He said that while China’s leader was “embarrassed” about the balloon incident, what “he was really upset about” was Biden’s efforts since taking office to bring the leaders of the Quad – the United States, India, Australia and Japan – closer together to serve as a counterweight to a more assertive China.

“He called me and told me not to do that because it was putting him in a bind,” Biden said, referring to the Chinese president. “We’re just trying to make sure the international rules of air and sea lanes remain open.”

The White House’s increased engagement with the leaders of the Quad, formally known as the Quadrilateral Security Dialogue, are part of a broader strategy by the US to elevate its diplomatic outreach to countries in the South Pacific and reengage with that part of the world.

The region has taken on a greater importance for Washington as China has become increasingly assertive over its territorial claims in the area, expands its naval capabilities and militarizes islands in the South China Sea.

“Now we have India, Australia, Japan and the United States working hand in glove in the South China Sea, in the Indian Ocean. We have a situation where I’ve met with all 50 of the major maritime states in East Asia,” Biden said in California. (CNN)

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