National Security Adviser Robert O’Brien said it wouldn’t be a surprise if Russia wanted to boost Sen. Bernard Sanders’ presidential campaign, pointing out that Mr. Sanders honeymooned in the old Soviet Union.

Mr. O’Brien also said in an interview airing Sunday he hasn’t seen analysis from the intelligence community showing that Russia is trying to interfere in the 2020 election to boost President Trump.

“Well, there are these reports that they want Bernie Sanders to get elected president. That’s no surprise. He honeymooned in Moscow,” Mr. O’Brien said in an interview for ABC’s “This Week.”

Mr. Sanders said late last week that he was briefed about a month ago about Russian interference attempts. The Washington Post reported that Russia is trying to help Mr. Sanders’ presidential campaign in a bid to interfere in the Democratic contest.

The Vermont senator condemned the effort and told Russian President Vladimir Putin to “stay out of American elections.”

Mr. O’Brien also said he hasn’t seen intelligence that Russia is trying to interfere in the 2020 elections to help get Mr. Trump re-elected.

“If it’s out there, it’s something I haven’t seen,” he said. “Our message to the Russians is stay out of the U.S. elections. We’ve been very tough on Russia and we’ve been great on election security. So I think it’s a non-story.”

He said he’s only seen secondhand “press reports” on a recent House briefing in which intelligence officials reportedly warned Congress that Russia is trying to interfere in the 2020 election to get Mr. Trump re-elected.

“What I will tell you is that I do think the Russians and the Chinese and others like to sow disruption in the American electorate,” Mr. O’Brien said. “And that doesn’t mean because they prefer a particular candidate. It’s because these are autocratic regimes that don’t believe in democracy and they’d like to see Americans at each other’s throat.”

Shortly after the briefing, acting director of National Intelligence Joseph Maguire was ousted in favor of Richard Grenell, the U.S. ambassador to Germany.

In a separate interview, Mr. O’Brien disputed the idea that Mr. Maguire was “pushed out” and pointed out that his term was ending in a few weeks.

“I have a tremendous amount of respect for him, as does the president,” Mr. O’Brien said in an interview for CBS’s “Face the Nation.”