Trump marks one year of Mueller probe with 'No Collusion' tweet

Donald Trump marked the one-year anniversary of special counsel Robert Mueller's probe into ties between the president's campaign team and Russia with a trademark tweet, reiterating "there is still No Collusion." "Congratulations America, we are now into the second year of the greatest Witch Hunt in American History...and there is still No Collusion and No Obstruction," Trump tweeted.

The Republican president has repeatedly insisted he's the target of a "witch hunt" and denied any collusion between Team Trump and Moscow to win the presidency against former Democratic rival Hillary Clinton.

In a follow-up tweet, Trump also revived claims that former president Barack Obama's administration spied on his campaign, after the FBI in 2016 launched its investigation into ties between the Republican camp and Russia.

"Wow, word seems to be coming out that the Obama FBI 'SPIED ON THE TRUMP CAMPAIGN WITH AN IMBEDDED INFORMANT,'" the president tweeted, misspelling the word "embedded." The tweet alluded to a report in The New York Times that said at least one government informant met several times with two Trump campaign advisers under investigation by the FBI, Carter Page and George Papadopoulos.

The Times said the FBI probe, codenamed "Crossfire Hurricane," began when two FBI agents secretly interviewed Australia's ambassador in London about a wine-fueled conversaation with Papadopoulos in which the Trump adviser suggested he knew in advance about the Russian meddling.

"As these revelations are making their way forward, it looks like the Trump campaign may in fact have been surveiled," White House counselor to the president Kellyanne Conway told Fox News Thursday. "As the president likes to say, we'll see what happens." "I think those who have been digging and conjecturing for over a year should be careful what they wish for." Since his appointment on May 17, 2017, Mueller -- a veteran prosecutor and former FBI director -- has kept his silence on the investigation.

But his team has notched 22 indictments, including those of former Trump national security advisor Michael Flynn and former campaign chairman Paul Manafort.

Mueller was given the reins of the probe shortly after Trump sacked James Comey as FBI director.

The special counsel has requested an interview with Trump -- a proposal the White House has thus far not accepted, as his lawyers debate the risks.

A leaked list of questions Mueller's team submitted to the White House suggests the special counsel is analyzing whether Trump obstructed justice -- notably by firing Comey last year and his attempt to shield Flynn.

Also on the table is how much Trump knew of his team members' contacts with Russia -- and what those contacts entailed.