US President Donald Trump on Monday demanded an apology over the Russia investigation rocking his presidency, as he kept up a days-long attack on Barack Obama for his handling of intelligence about election meddling by Moscow.
In a storm of morning tweets, Trump charged that his predecessor "colluded and obstructed" by failing to act after the CIA informed him Russian President Vladimir Putin personally ordered an operation to help defeat Trump's Democratic rival Hillary Clinton in the November vote.
"The real story is that President Obama did NOTHING after being informed in August about Russian meddling," Trump wrote. "With 4 months looking at Russia under a magnifying glass, they have zero 'tapes' of T [Trump] people colluding. There is no collusion & no obstruction. I should be given apology!"
"The reason that President Obama did NOTHING about Russia after being notified by the CIA of meddling is that he expected Clinton would win, and did not want to 'rock the boat.'"
"He didn't 'choke,' he colluded or obstructed, and it did the Dems and Crooked Hillary no good," Trump tweeted, alluding to a Washington Post article that laid out the timeline of Obama's response to the Russian threat.
Trump hit out in a flurry of weekend tweets and a televised interview following the Friday publication of the behind-the-scenes account by the Post.
The paper reported that the previous administration issued four warnings to Moscow -- including one Obama delivered directly to Putin -- causing Moscow to pull back on possible plans to sabotage US voting operations.
But it said Obama opted to leave countermeasures for later, for fear of being seen as interfering in an election he was confident Clinton would win.
After Trump's shock victory in November, some Obama administration officials expressed regret at the lack of tougher action.
Some Democrats saw abundant irony in Trump blaming Obama for indecisiveness against a Russian operation he himself has long seemed to play down -- including when he fired FBI chief James Comey in May over his handling of allegations of meddling, and possible collusion with Trump's campaign.
But others have joined in the criticism, including Adam Schiff, the ranking Democrat on the House Intelligence Committee, who said at the weekend that Obama's administration had made a "serious mistake."