The federal law enforcement investigation into possible ties between Russia and Trump associates has identified a current White House official as a significant person of interest, according to a Friday report in the Washington Post.

Sources familiar with the matter told the Post that the senior White House adviser in question is also someone close to the president. The report came moments after President Trump departed on Air Force One for his first foreign trip. The report also comes on the heels of a week of whirlwind developments for the White House, including reports that Mr. Trump divulged sensitive information to Russian officials and asked then-FBI Director James Comey to drop an investigation into former national security adviser Michael Flynn.

Deputy Attorney General Rod Rosenstein on Wednesday announced former FBI Director Robert Mueller will be the special counsel heading up the FBI investigation, as the investigation appears to be gaining momentum. Mr. Trump, the day after firing FBI Director James Comey, told Russian diplomats that firing that "nut job" Comey relieved pressure on him, according to a report the New York Times dropped moments before the Post's story.

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"I faced great pressure because of Russia. That's taken off," the president reportedly said.

Three current officials in the Trump administration have acknowledged contact with Russians. Those officials are Jared Kushner, Mr. Trump's son-in-law and senior adviser to the president, along with Attorney General Jeff Sessions and Secretary of State Rex Tillerson, who are cabinet members.

"As the president has stated before - a thorough investigation will confirm that there was no collusion between the campaign and any foreign entity," White House Press Secretary Sean Spicer said in a statement in response to the Post story.

The Russia story has plagued Trump's White House for months. The Trump campaign had at least 18 undisclosed contacts with Russians during the 2016 race. Flynn was forced out of the White House in February after he misled Vice President Mike Pence about his contact with Russian officials.

A source has told CBS News there is a "whole lot of interfering" in the Russia probe.

This is a developing story.

CBS News' Rebecca Shabad and Arden Farhi contributed to this report.