By Dana Bash, Jeremy Herb and Jim Acosta | CNN

The intelligence community’s top election security official delivered a briefing to lawmakers last week warning them that the intelligence community believes Russia is already taking steps to interfere in the 2020 election with the goal of helping President Donald Trump win, three sources familiar with the matter tell CNN.

Last week’s briefing, led by election security official Shelby Pierson and first reported by The New York Times, addressed the overall picture of Russia’s efforts, including hacking, weaponizing social media and attacks on election infrastructure, one of the sources said.

The briefers said Russia does favor Trump, but that helping Trump wasn’t the only thing they were trying to do as it was also designed to raise questions about the integrity of the elections process, the source added.

House Republicans got very upset during the briefing, another source said.

After the briefing, Trump became upset with outgoing acting Director of National Intelligence Joseph Maguire, a source familiar with the matter told CNN. Trump was concerned the Democrats present would use the briefing against him, reported the Times, citing people familiar with the exchange.

On Wednesday, Trump announced he was naming Richard Grenell, a staunch loyalist and current US ambassador to Germany, as acting DNI despite him not having experience in intelligence. Two administration officials told the Times the timing of the Grenell announcement and Russia intelligence report is coincidental.