The Department of Justice is expanding a probe into alleged FBI misconduct to include President Trump's claims that there may have been a 'mole' within his campaign reporting back to the feds.

White House Press Secretary Sarah Sanders said in a Monday afternoon statement that after a meeting with Trump this afternoon, DOJ officials agreed to ask the department's Inspector General to look into 'irregularities' within the FBI's 'tactics concerning the Trump Campaign.'

'It was also agreed that White House Chief of Staff Kelly will immediately set up a meeting with the FBI, DOJ, and DNI together with Congressional Leaders to review highly classified and other information they have requested,' she said in a statement.

The announcement followed a meeting between Trump, his FBI director, the deputy attorney general and the director of national intelligence this afternoon.

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President Donald Trump is meeting with his FBI Director, the Deputy Attorney General and the Director of National Intelligence this afternoon

The previously planned sit-down with Chris Wray, Rod Rosenstein (pictured) and Dan Coats is to discuss a response to congressional requests

Trump is expected to bring up his demand, however, that the Justice Department examine whether his 2016 presidential campaign was 'infiltrated or surveilled' by the FBI under the previous administration.

It had been described as previously as a planned sit-down with Chris Wray, Rod Rosenstein and Dan Coats to discuss congressional requests for information.

Trump was expected to bring up his demand, however, that the Justice Department examine whether his 2016 presidential campaign was 'infiltrated or surveilled' by the FBI under the previous administration.

He said Sunday that he would officially confront DOJ today about reports that an informant contacted the campaign with the intent of entrapping his associates.

Prior to the Monday meeting at the White House, the Department of Justice said it had heeded the president's request, with spokeswoman Sarah Flores telling CNN that DOJ would look into allegations of 'impropriety or political motivation' in the FBI's conduct.

The White House confirmed that Rosenstein, Wray and Coats were all on the property on Monday afternoon. Rosenstein lingered for more than an hour, although not all the time he spent at 1600 Pennsylvania Avenue was with Trump.

Wray and Coats arrived separately from Rosenstein. They were seen walking into the meeting at the same time.

Trump said Sunday that he would instruct the Justice Department to determine whether former President Barack Obama's administration was behind the effort after a morning spent tweeting about the Russia probe.

In a Saturday tweet Trump hinted that the meeting about providing documents was related to his repeated, and unverified, claims that there may have been a 'mole' inside his campaign who was put there by law enforcement in a serious abuse of power.

'If the FBI or DOJ was infiltrating a campaign for the benefit of another campaign, that is a really big deal,' he tweeted. 'Only the release or review of documents that the House Intelligence Committee (also, Senate Judiciary) is asking for can give the conclusive answers. Drain the Swamp!'

FBI Director Christopher Wray (right) arrives at the West Wing of the White House for a meeting on FBI investigations into the 2016 Trump presidential campaign

Director of National Intelligence Dan Coats departs after a meeting with President Donald Trump on FBI investigations into Russia and the 2016 Trump presidential campaign

The following day he said that if special counsel Robert Mueller's probe continues into the fall Democrats 'should easily be able to take it into the Mid-Term Elections where they can put some hurt on the Republican Party.'

'Don’t worry about Dems FISA Abuse, missing Emails or Fraudulent Dossier!' he carped, making references to FBI surveillance on one of his campaign associates, Hillary Clinton and the dirty dossier that her campaign helped to fund on him.

The tweets came after multiple reports the FBI dispatched a confidential source to speak with some of his campaign advisers about the possible ties to Russia.

Trump has been on a Twitter firestorm about the issue, charging the FBI planted 'at least one' spy in his campaign in order to derail his White House aspirations by ginning up a phony reason to criminally investigate him.

The president has long claimed that the Obama administration spied on his presidential efforts but offered no proof to back it up.

His numerous and loud allegations have led to questions about why he hasn't ordered an investigation into the matter.

Trump answered that in his tweet on Sunday, saying he would do just that.

'I hereby demand, and will do so officially tomorrow, that the Department of Justice look into whether or not the FBI/DOJ infiltrated or surveilled the Trump Campaign for Political Purposes - and if any such demands or requests were made by people within the Obama Administration!' he wrote.

His demand, however, raises additional questions about whether he's started a political witch hunt within the government and whether this is the start of a rolling call for additional probes into the 2016 campaign.

Former Obama spokesman Tommy Vietor ‏said Trump crossed a 'massive red line' with the demand for a probe,

'Trump is forcing DOJ to conduct a politicized investigation - something he himself conceded he shouldn't do. Someone in the Republican Party needs to stand up to this bullshit right now,' Vietor tweeted on Sunday.

President Trump is demanding the Justice Department investigate whether the FBI or the department 'infiltrated' his presidential campaign for 'political purposes.'

Sen. Mark Warner, the top Democrat on the Senate Intelligence Committee, said on CBS' 'Face the Nation' that he had not seen any evidence to suggest there was an informant inside the Trump campaign. He added that any effort to reveal the identity of a secret FBI source would be illegal and should be prosecuted.

'The first thing you learn when you get involved with the intelligence community is that you need to protect sources and methods and that if you were to out or to burn such an agent, that person's life could be in jeopardy,' he said. 'And I find it outrageous that the president's allies are in effect playing fast and loose with confidential information.'

Trump was on a Twitter bender on Sunday, spending the morning tweeting rants about special counsel Robert Mueller's investigation into alleged Russian influence in the 2016 election and about a bombshell New York Times article that revealed Russia may not have been the only country interested in influencing the presidential contest.

But his demand for an investigation comes after reports that an American academic who met with Trump's advisers in 2016 could have been an FBI informant for its probe into the campaign's alleged collusion with Russian.

Both the New York Times and Washington Post have reported the FBI made use of a U.S.-born academic working in the UK as an informant, and that he met with Carter Page and George Papadopoulos, two Trump aides suspected of dealing with the Russians.

The Daily Caller also reported that both Page and Papadopoulos met in 2016 with an American professor at Cambridge University, which it named as Stefan Halper. He asked several questions about Russia that prompted suspicions.

Following the reports and naming of the professor, Trump called for the release or review of related documents to the House and Senate Intelligence Committees.

Stefan Halper is a Cambridge Academic and has been named in several reports as an FBI informant on the Trump campaign. He is pictured in an undated image speaking at the Oxford Union debating society

Following the reports and naming of the professor, Trump tweeted: 'If the FBI or DOJ was infiltrating a campaign for the benefit of another campaign, that is a really big deal'

Papadopoulos revealed in a plea agreement to having been told by an apparent Russian agent that the Putin government had access to a raft of hacked Hillary Clinton emails before this was made public. He has since pleaded guilty to lying to the FBI.

Page, meanwhile, was under surveillance by the FBI at the time he met with Professor Halper, who had links to both the CIA and MI6.

Papadopoulos first met Halper after the academic invited him to England in September 2016 to discuss energy issues, two sources familiar with his account told NBC News.

The Trump aide found Halper's behavior during these meetings suspicious, the sources said, and also noticed that the academic's young assistant appeared to flirt with him both during and after the exchanges.

Papadopoulos said Halper, who is now retired, randomly brought up Russians and Clinton's emails, adding to his suspicions.

Page told the Daily Caller he met with Halper several times, including on the academic's farm in Virginia. However, Page told NBC he did not find these encounters concerning.

Halper also met with a third Trump campaign official, to whom he reportedly expressed interest in helping the president's campaign.

There is no public evidence that Halper was an FBI informant, and official sources have refused to comment on the subject. Halper has not provided any comment on the issue.

Trump's attorney, former New York City Mayor Rudy Giuliani, admitted on CNN on Friday that there's no proof the Obama administration had a mole inside the Trump campaign during the president's 2016 run.

'First of all, I don't know for sure – nor does the president – if there really was one,' Giuliani said. 'For a long time we've been told that there was some kind of infiltration. At one time the president thought it was a wiretap. ... but we've never been notified that he was on a tap or an intercept.'

George Papadopoulos was one of three Trump aides that met with Professor Halper during 2016

Carter Page, a Trump adviser who was under FBI surveillance before the 2016 election. He is pictured on December 12, 2016, in Moscow

The academic has long-established connections to both British and American intelligence services.

He worked closely with former MI6 chief Sir Richard Dearlove at the Cambridge Security Initiative, an intelligence consulting group.

Meanwhile, his father-in-law was Ray Cline, who served as director of the CIA's bureau of intelligence and research. Halper also worked with a team of former CIA officials on George H.W. Bush's failed presidential bid.

Allegations that the FBI planted an informant in the Trump campaign have angered the president.

In a series of late night calls to allies, including Fox News host Sean Hannity, Trump has used the reports as evidence that the so-called deep state of career government officials has been working against him.

The president thrust the issue into the limelight with a tweet on Friday.

He quoted Fox News anchor David Asman, who said: 'Apparently the DOJ put a Spy in the Trump Campaign. This has never been done before and [is not] by any means necessary, they are out to frame Donald Trump for crimes he didn't commit'.

Trump has frequently fumed about the Russia probe even while in White House meetings this week about other topics.

Trump's lawyer, Rudy Giuliani, told CNN on Friday neither he or Trump actually knew for sure if there was an informant or not

Trump tweeted a quote from Fox News anchor David Asman, claiming the DOJ would 'frame him for crimes he didn't commit'

Talk of the reported FBI source has rocketed through the conservative media, with several people putting forward Halper as the likely suspect.

Hannity discussed the issue on his show Wednesday - and was a centerpiece of Giuliani's attacks on Friday.

'I want to know because I believe, if there was an embedded person, that person cleared us because the FBI cleared us,' Giuliani told CNN. 'I wonder what the heck is the legitimacy of the Mueller investigation in the first place.'

Trump allies have increasingly pushed for ways to paint Mueller and his investigators as political actors in an effort to discredit his findings or justify his possible dismissal.

A number of Trump outside advisers - including former chief strategist Steve Bannon - have stepped up their attacks on the Department of Justice, calling for it to release more documents to the White House while saying a confidential source has worked against Trump.