President Donald Trump vented about the probe into Russia's role in the 2016 election in a series of Monday morning tweets, hammering predecessor Barack Obama for his response.

Asking for an "apology," Trump denied that his campaign associates colluded with Russia or that he obstructed the federal investigation into Moscow's actions. He argued that Obama's delayed response is "the real story."

Trump has repeatedly lashed out and deflected criticism following reports that special counsel Robert Mueller, who is overseeing the FBI's Russia investigation, is looking into whether Trump attempted to obstruct justice. The president has faced increasing pressure since he abruptly fired former FBI Director James Comey last month.

Trump: The reason that President Obama did NOTHING about Russia after being notified by the CIA of meddling is that he expected Clinton would win..

Trump: ...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: The real story is that President Obama did NOTHING after being informed in August about Russian meddling. With 4 months looking at Russia...

Trump: ..under a magnifying glass, they have zero "tapes" of T people colluding. There is no collusion & no obstruction. I should be given apology!

Comey testified that Trump asked him for loyalty — which an FBI chief does not owe a president — and made a statement that he interpreted as a request to "drop" a probe into former national security advisor Michael Flynn. Trump denied making those statements.

Trump's criticism of Obama has increased since The Washington Post published a detailed report about Obama's reluctance to speak publicly about, or retaliate against, Russia's actions after the CIA informed him of them in August. Obama worried that any response before the election could "provoke an escalation" from Russian President Vladimir Putin or "be perceived as political interference in an already volatile campaign," according to the Post.

One former senior Obama administration official told the newspaper that "we sort of choked."

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