Donald Trump dismisses US intelligence briefing warning Russia is working to boost his re-election

Donald Trump has dismissed a US intelligence assessment that Russia is meddling in the 2020 election to help his re-election as a Democrat "hoax", amid a row over a briefing with Congress last week.

"Another misinformation campaign is being launched by Democrats in Congress saying that Russia prefers me to any of the Do Nothing Democrat candidates who still have been unable to, after two weeks, count their votes in Iowa," the president tweeted, adding "Hoax number 7!"

It comes after America's top election security official, Shelby Pierson, warned the House Intelligence Committee that the Kremlin was interfering in the 2020 presidential campaign to aid Mr Trump's re-election in a classified briefing on February 13.

More than two dozen Democrats and Republicans sit on the committee, and the details of the briefing are thought to have been related to Mr Trump.

The US president was furious with his acting director of national intelligence (DNI), Joseph Maguire, and his aides for speaking to Congress and accused them of being "disloyal",  according to the Washington Post.

White House sources suggested the briefing effectively thwarted Mr Maguire's chances of filling the role permanently.

Mr Trump was impeached in December over accusations that he coerced ally Ukraine into helping him cheat in the 2020 election, withholding military aid considered vital to the former Soviet republic in its war with Russia.

Since he was acquitted by the Republican-led Senate, an emboldened Mr Trump has been purging the Justice Department, National Security Council and Pentagon of staff he considers disloyal.

Casualties have included NSC staffer Lieutenant Colonel Alex Vindman and EU ambassador Gordon Sondland - both key witnesses in the impeachment inquiry - Vindman's twin brother, an NSC lawyer who wasn't involved, and Pentagon policy chief John Rood.

The president announced on Wednesday that he was replacing Mr Maguire with Richard Grenell, who is the US ambassador to Germany and a vocal Trump loyalist.

Some members of the intelligence community have expressed disquiet over the announcement, as the DNI oversees all of America's intelligence agencies and is usually filled by someone with intelligence gathering or military experience.

Mr Grenell, 53, has a background in communications, with no relevant intelligence or top-level management experience.

He has also previously cast doubt on the extent of Russia's election interference efforts, saying that Moscow's activities were nothing new.

In a statement announcing the move, the White House said: "He is committed to a non-political, non-partisan approach as head of the Intelligence Community, on which our safety and security depend.''

Senator Ron Wyden, a Democrat on the intelligence committee, accused Mr Trump of prioritising "unquestioning obedience over the safety of the American people."

Mr Trump has declined to hire a permanent replacement for Dan Coats, who stepped down as the DNI in August 2019 after standing firm on the intelligence community's conclusion that Russia interfered in 2016 to back Trump over Hillary Clinton.

Mr Trump has said he will name a permanent director, which requires a confirmation vote in the US senate, at a later date.

The president initially told reporters earlier this week that he was considering Republican Doug Collins as his permanent director of national intelligence, but the congressman said he was not interested in the post.

Mr Trump later tweeted: “Four great candidates are under consideration at DNI,” without naming Mr Collins. “Decision within next few weeks!”