A Cambridge University professor with CIA contacts who President Trump calls a 'spy' kept tabs on key Trump campaign contacts – and once tried to establish that Trump foreign policy advisor George Papadopoulos was linked to the Russia-based hacking of emails belonging to Hillary Clinton.

The academic, Stefan Halper, had contacts with Trump campaign advisers including Papadopoulos, Carter Page and former national campaign co-chairman Sam Clovis.

He dined with Papadopoulos, bringing along his Turkish assistant, Azra Turk.

Halper, 73, cut a colorful figure as he strolled through diplomatic, academic, and espionage circles, having served in the Reagan, Ford, and Nixon administrations.

Owing to his girth, he earned the nickname 'the walrus' from some who know of his exploits.

Cambridge University academic Stefan Halper tried to get three Trump campaign aides to trust him in 2016, including then-foreign policy adviser George Papadopoulos

During one of their dinners, Halper asked Papadopoulos whether he was involved in Russian hacking of Democratic emails, The Daily Caller reported.

'George, you know about hacking the emails from Russia, right?' he asked, according to multiple news reports.

After Papadopoulos denied it, Halper grew frustrated.

Papadopoulos sat down in London for dinner with Halper and was asked what he knew about Russians hacking Hillary Clinton's emails – a question that now appears part of a spy plot

The odd question would fit with a scenario suggested over the weekend by conservative pundits, in which Halper – acting on the FBI's behalf – attempted to confirm Papadopoulos' complicity but came up empty-handed.

Papadopoulos also claimed Halper's assistant, Turk, flirted with him during their meetings, according to the Daily Caller.

His contacts with Trump's campaign took place while the FBI was undertaking a probe since revealed to be called 'Crossfire Hurricane' seeking to uncover ties between the Trump campaign and Russia. It later would morph into the Russia probe being overseen by Special Counsel Robert Mueller.

The Washington Post and New York Times both reported Halper's existence as an informant but did not publish his identity. Halper's name had been circulating among reporters and others in Washington for weeks – as Republicans in Congress put pressure on the Justice Department to release the name and work product of the the FBI's informant.

Halper, who has longstanding MI6 and CIA ties, married into the family of U.S. intelligence legend Ray Cline – famed for being the chief CIA analyst during the Cuban Missile Crisis.

Halper also cultivated a relationship with Carter Page, a Trump aide, and invited him to visit his home in Virginia

Cultivating a rapport with Papadopoulos to gain his confidence was apparently important enough to the FBI that Halper offered him a payment for an academic paper – as a pretext for having in-person meetings.

Agreeing to pay Page $3,000 for a policy paper about erergy issues in Turkey, Israel and Cyprus gave him a reason to spend even more money to fly him to London to discuss the project during meetings and at least one dinner.

They met at the Travellers Club, a gentleman's club there. Later, Turk tried to meet with Papadopoulos in his home town of Chicago.

Halper had asked Papadopoulos about writing the paper on about 'a disputed gas field in the eastern Mediterranean Sea,' according to the New York Times.

Papadopoulos was the first figure to plead guilty in the Mueller probe. He admits he lied to the FBI about his contacts with another professor, Joseph Mifsud, a London-based academic originally from Malta who had Kremlin contacts.

Papadopoulos says it was Mifsud who told him the Russians had dirt on Hillary Clinton.

President Trump smelled blood over the weekend, demanding a Justice Department inquest into whether or not the Obama administration spied on his campaign organization for partisan purposes.

President Donald Trump took the new revelations about an informant to demand a Justice Department investigation of the FBI's conduct

STEFAN HALPER'S TARGETS IN TRUMPWORLD CIA-linked Cambridge professor Stefan Halper tried to get close to at least three Donald Trump advisers in 2016 and 2017, reportedly to learn for the FBI whether they were links between the Trump campaign and Moscow. Here's a look at some of the key figures in the latest drama in Trump-world: Stefan Halper Stefan Halper is an an academic who cultivated figures in Donald Trump's campaign Carter Page Carter Page was a Trump advisor that drew immediate interest of investigators due to his longstanding Russia ties. The New York Times reported that a government informant met with him several times during the campaign. He is mentioned repeatedly in the Steele dossier, and was the subject of a Foreign Intelligence Surveillance Court warrant that authorized monitoring of his activities. Former Trump foreign policy advisor Carter Page makes a presentation titled 'Departing from Hypocrisy: Potential Strategies in the Era of Global Economic Stagnation, Security Threats and Fake News' during his December 2016 visit to Moscow George Papadopoulos Papadopoulos was one of just a handful of early foreign policy advisors identified by President Trump at the start of his campaign. His boozy chat with the top Australian diplomat in London helped kick off the Russia probe. Halper met with him several times during the campaign. Halper arranged for him to get paid $3,000 for a policy paper on energy issues, and emailed him about the status of the 'collusion' investigation George Papadopoulos, whose boozy chat with the top Australian diplomat in London helped kick off the Russia probe Sam Clovis Halper met with Clovis offering to assist the campaign with his foreign policy expertise. Their conversations over coffee in northern Virginia focused on China, according to Clovis' lawyer. He served as co-chair of Trump's campaign and according to court records recruited Papadopoulos, a young aide without a long resume, to join the campaign. Sam Clovis ran for office in Iowa and hosted a conservative radio show, then co-chaired Donald Trump's campaign. He recruited George Papadopoulos to join the effort Advertisement

'If the FBI or DOJ was infiltrating a campaign for the benefit of another campaign, that is a really big deal,' he tweeted Saturday, demanding the FBI turn over key documents to Republicans in Congress.

Halper could become Exhibit A if the GOP turns political spycraft into a midterm election issue.

An email obtained by the Daily Caller shows Halper reaching out to Page, whose Russia contacts drew the attention of FBI investigators in the early days of the Trump-Russia probe.

'I thought I'd write as the summer wears on to see how you are,' Halper wrote last year.

'It seems attention has shifted a bit from the 'collusion' investigation to the 'contretempts' [sic] within the White House,' he wrote July 28, 2017.

'I must assume this gives you some relief,' he added. 'Be in touch when you have the time. Would be great to catch up.'

Halper invited Page to visit his farm in Virginia, part of what may have been an extended effort to cultivate him as a source of information for the FBI.

'There has been some speculation that he might have tried to reel me in,' Page told the Washington Post. 'At the time, I never had any such impression.'

Page told The Daily Caller that Halper ingratiated himself by claiming to have been a longtime friend of Paul Manafort, who was at the time the Turmp campaign's chairman.

But a person close to Manafort told the publication that the pair hadn't seen one another since the Gerald Ford administration.

And Halper 'rolled his eyes' in faux solidarity with Page in mid-2016 when they discussed a letter from then-Senate Minority Leader Harry Reid to then-FBI Director James Comey, in which the Democratic senator suggested Page might be a Russian agent.

Halper's effort to nurture a similar relationship with Clovis met with less success. Their sole meeting was a small-talk affair.

Clovis had earlier recruited Page and Papadopoulos into the Trump campaign, making him a logical person of interest to any investigators who believed the pair were Trumpworld's conduits to Moscow.

Halper tried to keep up the relationship after the election, penning a note of congratulations to Clovis.

It's not known whether Halper was on the FBI's payroll. But according to public records, he has received six-figure payouts from a shadowy Department of Defense sub-agency in 2016 and 2017.

The Pentagon's Office of Net Assessment paid him $129,000 last year and $282,000 the year before, while the Trump capaign was in full swing.

Halper is one of three men to have resigned from a seminar at Cambridge, fearing it was being targeted by Russia as a way to gain influence, the Telegraph reported in 2016. They left following concerns that a Russian journal provided support to the seminar, constituting an 'unacceptable Russian influence,' according to Halper.

Among the attendees at the Friday seminar, known as the Cambridge Intelligence Seminar, are Lt. Gen. Mike Flynn, Trump's fired national security advisor, who pleaded guilty to lying to the FBI and is cooperating with the Mueller probe.

Halper also figures into a campaign imbroglio from decades ago. As the Intercept reported, he worked on the Ronald Reagan presidential campaign, where his role involved gathering information from within the Carter White House. A New York Times story at the time described it as am operation 'to gather inside data on Carter' overseen by retired Central Intelligence Agency figures.

It was overseen by Bush, who had been director of the CIA.