As President Trump sought to blame the Obama administration for missing Flynn's links with Russian contacts, the former administration revealed that Obama warned Trump personally about the embattled retired general.
Flynn lasted just 24 days as national security adviser before being fired by Trump for not telling the truth about contacts he had had with Russia's ambassador to Washington.
Obama hired, and fired, Flynn as the head of the Defense Intelligence Agency.
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Obama warned Trump about Flynn's conduct during a first meeting in the Oval Office, a warning "based on Flynn’s role as head of DIA," a former administration official said.
Despite that message, Trump hired Flynn to the high profile job of national security advisor - the president's top foreign and security policy aide - before firing him for misleading the administration about his contacts with Russia.
Later on Monday, former acting attorney general Sally Yates is expected to tell a Senate inquiry that she also explicitly warned Trump's team in January that Flynn could be compromised by once-concealed communications with Russia's US ambassador.
Trump, who fired Yates soon after taking office, fired off a series of pre-emptive strikes ahead of her appearance on Capitol Hill, accusing Obama of enabling Flynn and assailing Yates for allegedly leaking classified information.
"General Flynn was given the highest security clearance by the Obama Administration," Trump tweeted early Monday.
"Ask Sally Yates, under oath, if she knows how classified information got into the newspapers soon after she explained it to WH Counsel," he said, apparently referring to the counsel's office, an in-house legal team.
