WASHINGTON — Members of the House and Senate are receiving classified briefings Tuesday on election security, the first since intelligence officials warned lawmakers of new Russian efforts to interfere in the 2020 election.

The briefings come amid voting in the 2020 presidential primaries and after intelligence officials told lawmakers last month that Russia is still trying to to sow discord in the American electorate.

Lawmakers were told in a classified briefing in February that Russia continues to have a preference for President Donald Trump, after also trying to help him in the 2016 presidential contest, according to officials familiar with the briefing. Sen. Bernie Sanders, who is running in the Democratic primary to challenge Trump, acknowledged that he was also briefed by U.S. officials about Russian efforts to boost his candidacy.

The Russian efforts are aimed at undermining public confidence in the integrity of U.S. elections and stirring general chaos in American politics, intelligence experts say.

Intelligence officials from seven agencies — including the Department of Homeland Security, the Department of Justice and multiple intelligence agencies — will brief the House and then the Senate Tuesday afternoon.

The Russian interference is expected to be a topic of questioning, along with efforts to secure state and local election systems that were scanned by Russia in 2016. There is no evidence that any votes were changed.

Shortly after the news reports of Russian interference in the 2020 contest last month, House Speaker Nancy Pelosi tweeted: “We await the election security briefing for Members on March 10.”

One official who will not be briefing lawmakers is Richard Grenell, a Trump loyalist who is serving as acting national intelligence director. Grenell, criticized by Democrats as being unfit for the job, was originally on the list of officials being sent to Congress by the Trump administration but was later replaced by another official from the office of the Director of National intelligence, according to two people familiar with the schedule. The people requested anonymity to discuss the classified briefing,

The office of the DNI later denied in a tweet that Grenell backed out of the briefing.

Trump has nominated Texas Rep. John Ratcliffe as a permanent replacement for Grenell, but it’s unclear if he will have the needed support in the Senate for confirmation. Trump also nominated Ratcliffe for the post last year, then withdrew the nomination after Democrats questioned his experience and news reports challenged the accuracy of Ratcliffe’s resume.

The president has long questioned whether Russia interfered in the 2016 elections and has called that theory a “hoax” despite the determination of the nation’s intelligence agencies that it happened. On Tuesday, he tweeted that “there is another Russia, Russia, Russia meeting today.”

Trump falsely said that the meeting would be headed by House Intelligence Committee Chairman Adam Schiff, “so I wouldn’t expect too much!” Trump has often criticized Schiff, who is not leading the briefing, since he led the House’s impeachment investigation.

Schiff tweeted in response that Trump was wrong, and that the officials providing the briefing are agency heads and senior officials.

“They are your own people,” Schiff tweeted to Trump. “We will insist on the truth, whether you like it or not.”