Putin often comments on political and social issues in the United States, often with sarcasm
White House lashes back following Russian President Vladimir Putin's snide 'support' of Kamala Harris AFP

A White House official flatly instructed Russian President Vladimir Putin to keep his nose out of the US election following his smirking "support" of Democratic presidential candidate Kamala Harris.

"The only people who should get to determine ... the next president of the United States are the American people," White House National Security Communications Advisor John Kirby told reporters at the Eastern Economic Forum in the Russian city of Vladivostok late Thursday.

The nation would "greatly appreciate" it if Putin would "A. Stop talking about our election, and B. Stop interfering in it," he emphasized.

Putin "shouldn't be favoring anybody one way or another," Kirby underscored.

A smirking Putin claimed earlier on Thursday at the summit that he was "supporting" Democratic presidential contender Kamala Harris, mocking her "infectious laugh," which has been roundly insulted by her Republican rival Donald Trump.

"Our 'favorite,' if I may say so, was the incumbent President Mr. Biden," said the smiling Putin.

"He was removed from the race, but he recommended that all his supporters support Ms. Harris. So, we will do the same, we will support her," he added before noting Harris's laugh.

Harris "laughs so expressively and infectiously" that it means "everything is fine with her," and she's unlikely to impose more sanctions on Russia, Putin grinned.

Donald Trump seemed befuddled by Putin's comment.

"I don't know if I'm insulted or he did me a favor," Trump said of Putin while outlining economic proposals to a group of New York City and Wall Street officials on Thursday.

Trump, who has long boasted of a special relationship with the Kremlin strongman, in May claimed that Putin would only release imprisoned Wall Street Journal reporter Evan Gershkovich to him once he won the White House.

"Vladimir Putin ... will do that for me, but not for anyone else," Trump boasted.

A Kremlin spokesperson responded at the time: "Naturally, Putin has no contact with Donald Trump."

Gershkovich was freed last month following negotiations with the Biden administration.

Kirby issued his remarks following indictments Wednesday of two employees at Russia Today on charges of attempting to interfere with U.S. elections through influencers on American social media.