The former British Ambassador to the United States was investigated for possibly leaking secret White House information to a married CNN journalist he was reportedly having an affair with.

Lord Kim Darroch, a married father of two, was said to have been engaged in an affair with former White House correspondent Michelle Kosinski, who had mysteriously begun releasing reports detailing inner communications and plans of the Trump administration.

U.S. government sources told The Sun that the Department of Justice (DoJ) launched an investigation into the former British diplomat after being “astonished” at the information released in a series of articles by Mrs Kosinski.

In July of 2019, Darroch resigned following leaks of his indiscrete diplomatic cables to the United Kingdom, which derided President Trump and his administration as “incompetent”, “dysfunctional”, and “clumsy”.

Days prior to Darroch’s resignation, President Trump had said: “The ambassador has not served the UK well,” adding: “I can say things about him but I won’t bother.”

A former top U.S. official told the British press that Mr Trump was referencing the DoJ investigation into the ambassador and his affair with the CNN reporter, saying: “The President never holds back, but out of respect to the UK he did on this occasion.”

A security source added: “The leaks of the cables last year were obviously deeply embarrassing and left Darroch no option but to resign once President Trump made his feelings clear.”

“But for the U.S. to investigate the most senior diplomat of its greatest ally on suspicion of leaking secret information is almost unprecedented,” the source said.

“Although the investigation found nothing over Darroch, the fact it happened is extraordinary.”

According to text messages seen by The Sun, Lord Darroch began his affair with Mrs Kosinski, who is also married, in 2018, meeting her in secret.

According to the report, Kosinski’s reports for CNN increasingly featured White House scoops, raising suspicions amongst senior officials, who previously described her as being “not well connected”.

Security officials suspected the now-former British ambassador of leaking info to Kosinski, detailing plans for then-CIA director Mike Pompeo to become the Secretary of State. Kosinski also allegedly learned of sensitive plans for Mr Pompeo to travel to North Korea to pressure the communist dictatorship to release three American captives.

“It was believed that no one on the U.S. side would leak this information,” a source said.

“It was critical for the American officials that this information did not get out. If it did, the North Koreans could have been spooked and the three Americans may never have been returned,” the source added.

Following the poisoning of ex-Russian double agent Sergei Skripal and his daughter in Salisbury, England, and the expulsion of Russian diplomats from Britain, Kosinski reported that the United States was also considering a move to expel Russian diplomats.

Later she revealed “new and exclusive” details about the situation, citing “a senior foreign diplomat”. She is said to have gone on to report that the U.S. was discussing sanctions against Russia for the poison attack.

“Kosinski knew about these sanctions before they were announced,” a former U.S. official said.

Amid growing concerns about her intimate knowledge of White House plans, security officials are said to have uncovered her alleged affair with Lord Darroch, prompting the investigation. Officials were said to be concerned that the affair could compromise Darroch to blackmail by hostile foreign actors.

The investigation ultimately cleared Darroch after failing to produce sufficient evidence against him. According to her LinkedIn page, Mrs Kosinski left CNN in February of 2020.

In response to the report, Brexit Party leader Nigel Farage called on the British government to launch an investigation into the former ambassador.

“We now know what [President Trump] really meant when he spoke after Darroch’s resignation. What a disgrace this man is — he was working to damage the special relationship,” Farage said.

“The British PM must investigate and, if necessary, strip him of all honours,” he demanded.

A Foreign Office spokesman said “All staff are expected to maintain the highest standards of behaviour. Any allegations of impropriety are thoroughly investigated.”

They added, however, that “No concerns regarding Lord Darroch and national security leaks were raised with the FCO either internally or by the intelligence community.”

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