FILE - In this Tuesday, Aug. 18, 2020, file photo, a person drops applications for mail-in-ballots into a mail box in Omaha,…
FILE - A person drops applications for mail-in ballots into a mailbox in Omaha, Nebraska, Aug. 18, 2020.

WASHINGTON - The White House is defending its efforts to protect the November presidential election from outside interference following a revelation that Russian “malign … actors” have been echoing President Donald Trump’s repeated warnings about potential election fraud.

"We're going to do everything we can to protect the sanctity of our election,” National Security Adviser Robert O’Brien told reporters Friday, adding the White House and the president have taken “unprecedented action” to protect the November vote.

FILE - National Security Adviser Robert O'Brien speaks to reporters outside of the West Wing of the White House in Washington, May 21, 2020.

"We've made it very clear to the Chinese, to the Russians, to the Iranians and others that haven't been publicly disclosed that anyone who tries to attempt to, that anyone who attempts to interfere with American elections will face extraordinary consequences," he said.

The assurances follow the release Thursday of a leaked Department of Homeland Security bulletin saying Russia is stoking fears that expanded mail-in voting will lead to a flawed election result.

“Since at least March 2020, Russian malign influence actors have been amplifying allegations of election integrity issues in new voting processes and vote-by-mail programs,” according to the bulletin, first obtained by ABC News.

“Russia is likely to continue amplifying criticisms of vote-by-mail and shifting voting processes amidst the COVID-19 pandemic to undermine public trust in the electoral process,” it said.

Trump has been raising concerns  about the use of mail-in ballots for months.

In June he tweeted the use of mail-in ballots would result in “the most RIGGED Election in our nations [sic] history.”

And earlier this week, he created controversy by appearing to urge his supporters to vote twice, through mail and again in person, to test the election system and ensure their votes count. To deliberately vote twice is illegal.

Top White House officials Friday defended the president’s comments about mail-in voting, describing them as justified.

“Obviously, there are tremendous concerns about mail-in ballots,” O’Brien said, suggesting that ballots were stacked in apartment buildings nationwide.

A Google News search by VOA turned up reports of only one incident in which some mail carriers in New Jersey had left mail-in ballots in apartment lobbies rather than in individual mailboxes.

The national security adviser said those worries should not be conflated with other threats to the upcoming election.

"Those concerns are very different than being concerned about foreign adversaries trying to influence our elections," O’Brien said, repeating the main threat is not from Russia.

"The intelligence community has made very clear, first you have China, which has the most massive program to influence the United States politically,” he said.

O’Brien also seemed to cast doubt on intelligence suggesting U.S. adversaries are taking sides.

"Some of them prefer Biden,” he said, referring to Democratic challenger, former Vice President Joe Biden. “Some people say some of them prefer the president."

"My position is it doesn't matter what these countries want, that any country that attempts to interfere with free and fair elections in the United States has to be stopped," O’Brien said.

Information shared with the public last month indicated senior officials in the U.S. intelligence community believe countries like Russia and China have clear preferences, and that Russia has been especially active.

FILE - Director of the National Counterintelligence and Security Center William Evanina speaks during the Reuters Cybersecurity Summit in Washington, Oct. 31, 2017.

“We assess that Russia is using a range of measures to primarily denigrate former Vice President Biden and what it sees as an anti-Russia ‘establishment,’” National Counterintelligence and Security Center Director William Evanina said in the August 7 statement.

“Some Kremlin-linked actors are also seeking to boost President Trump’s candidacy on social media and Russian television,” he added.

Evanina also said both China and Iran would prefer to see a Biden victory.

Beijing sees Trump as “unpredictable,” Evanina said, adding that Chinese officials understood the range of influence operations they have set in motion “might affect the presidential race.”

Trump, who has been frustrated by allegations that Moscow helped him win in 2016, has repeatedly dismissed suggestions Russia would like to see him win.

“We've taken stronger action against Russia than any other country in the world,” he told reporters late Friday during a wide-ranging briefing at the White House, while also arguing the threat from Russia has been exaggerated.

"It is interesting that everybody's always mentioning Russia,” Trump told reporters. "I don't mind you mentioning Russia, but I think probably China, at this point, is the nation you should be talking about, much more so than Russia."

U.S. officials have been promising that despite the myriad concerns, the upcoming presidential election will be “the most secure election in modern history,” though they have warned that unlike in past elections, final results may be delayed by what they expect will be a large number of mail-in ballots. 

U.S. intelligence and law enforcement officials have also said there is no intelligence to suggest any foreign country or anyone in the U.S. is actively trying to use mail-in ballots to rig the presidential election.