US officials have warned that Russia is attempting to help President Donald Trump and Democratic candidate Bernie Sanders ahead of November's US election, US media report.
A top intelligence official said Russia favoured Mr Trump, in a closed-door briefing to lawmakers on 13 February.
Mr Trump sacked his acting intelligence chief, Joseph Maguire, a week later.
President Trump said the reports were "another misinformation campaign" by his Democratic opponents.
The New York Times reported that Mr Trump was particularly angry that Adam Schiff, the Democrat who led the impeachment proceedings against him, was at the briefing.
In a separate report on Friday, the Washington Post said US officials have also told Vermont Senator Bernie Sanders that Russia is trying to help his presidential campaign.
The paper said President Trump and other US lawmakers have been informed of the attempted assistance, but it is not clear what form it has taken.
Responding to the report, Mr Sanders said he opposed Russia's efforts to "undermine American democracy". Addressing Russian President Vladimir Putin directly, Mr Sanders said:"Stay out of American elections."
Democratic presidential candidate Bernie Sanders on Friday warned Russia to stay out of U.S. elections after American officials had told him Moscow was trying to aid his campaign.