The swirling controversy over possible links between Donald Trump’s campaign team and Russia has taken a new twist after it was claimed the White House sought to stop a former senior official from testifying before congress.

The House Intelligence Committee has cancelled all meetings scheduled for this week, where it was due to hear testimony from, among others, former acting attorney general Sally Yates.

Ms Yates was forced to step down after refusing to enact Mr Trump’s Muslim travel ban. She had earlier told the Trump campaign that security advisor Michael Flynn may have left himself vulnerable to blackmail attempts from Moscow after lying about conversations with the Russian Ambassador to Washington.

The Washington Post said it had reviewed letters from the Department of Justice in which it told Ms Yates it considered much of her possible testimony to be barred from discussion at the committee hearing. It said this was because the topics were covered by the presidential communication privilege.

Ms Yates and other former intelligence officials had been asked to testify before the House Intelligence Committee this week, a hearing that was cancelled by the panel’s chairman, Congressman Devin Nunes.

The decision to cancel the hearing came amid criticism from Democrats after it was revealed that Mr Nunes, a Republican, travelled to the grounds of the White House to review intelligence reports and meet a secret source to bolster his claim that communications involving associates of Mr Trump were caught up in “incidental” surveillance.

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The top Democrat on the House Intelligence Committee, Congressman Adam Schiff, as well as the Democratic leaders in the House and Senate, have called on Mr Nunes to recuse himself from the committee's Russia probe.

In January, Ms Yates warned White House Counsel Don McGahn that statements made by White House officials about Mr Flynn’s contacts with the ambassador were incorrect, and could therefore expose the national security adviser to future blackmail.

Jeff Sessions presses Sally Yates on her need for independence from the White House

Jeremy Bash, a former chief of staff at both the Defence Department and CIA under Barack Obama, claimed Mr Nunes had come up with the story about travelling to the White House to block the testimony of Ms Yates.

“The real story, the real issue here, is not so much about the midnight run by the chairman onto the White House grounds, it’s really that they wanted to cancel the hearing this week,” Mr Bash told MSNBC.

“The hearing this week was going to hear from Sally Yates, the former acting attorney general, and I’m told that she had some very interesting things to tell the committee, to tell the public about when she told the White House counsel that Mike Flynn had, in fact, been lying to the vice president.”

He added: “She was only going to be able to speak those things in the context of a congressional hearing, and so the White House and the chairman needed to shut her down. This was an elaborately choreographed gag order on Sally Yates.”