 -- When the Department of Justice notified President Donald Trump and White House staff in January about concerns over National Security Adviser Michael Flynn’s contact with the Russian ambassador, Vice President Mike Pence was kept out of the loop, only learning about the matter last week through media reports, according to Pence’s press secretary.

Pence was made aware that he received "incomplete" information from Flynn only after reading a report about the circumstances in the Washington Post last Thursday and asking about the situation.

Two weeks had passed since the Justice Department first contacted the White House on Jan. 26 and Trump who was “immediately" informed, according to White House Press Secretary Sean Spicer.

"What I would tell you is that the vice president became aware of incomplete information that he had received on February 9th last Thursday night based on media accounts,” said Pence's press secretary Marc Lotter. “He did an inquiry based on those media accounts."

Using information provided to him by Flynn, the vice president publicly denied that the former general discussed U.S. sanctions on Russia with the Russian ambassador in an interview with CBS’s “Face the Nation” on Jan. 15.

Flynn wrote in his resignation letter that he "inadvertently briefed the Vice President Elect and others with incomplete information regarding my phone calls with the Russian ambassador."

Earlier in the day Tuesday, Spicer classified the "evolving and eroding" relationship between National Security Adviser Michael Flynn and Trump as what prompted the president to ask for Flynn's resignation.

"There's nothing that the general did that was a violation of any sort," Spicer said. "What this came down to was a matter of trust."

"When the president heard the information as presented by White House counsel, he instinctively thought Gen. Flynn did not do anything wrong, and the White House counsel's review corroborated that," Spicer said.

Spicer repeatedly said that nothing Flynn said in his calls with the ambassador was illegal, adding that "the president had no problem with the fact that he [Flynn] acted in accord to what his job was to be doing."

But Flynn's relationship with Trump "had eroded to the point where he felt he had to make a change," said Spicer, pointing to an unspecified "series of questionable instances."

Flynn offered his resignation Monday night. Tuesday's news conference was the first since then.

Flynn previously confirmed that he had spoken to the ambassador but denied that they discussed the sanctions that the United States imposed on Russia for its suspected interference in the 2016 presidential election.

It was later publicly disclosed that such a conversation did take place. According to a senior White House official, Flynn called Pence last Friday to apologize for misleading him about the conversation.

ABC News' Katherine Faulders contributed to this report.