US special counsel Robert Mueller has disputed the accuracy of a news report that said Donald Trump directed his lawyer Michael Cohen to lie to Congress.

Citing two unidentified law enforcement officials, BuzzFeed reported that the US president directed his long-term lawyer to lie about a Moscow real estate project and that Mr Trump personally instructed him to lie about the timing of the project.

The report does not cite specific errors, but says Mr Mueller’s investigators learned about Mr Trump’s directive “through interviews with multiple witnesses from the Trump Organisation and internal company emails, text messages, and a cache of other documents”.

In response to the Mueller team's statement, Mr Trump tweeted it was “a very sad day for journalism, but a great day for our Country!”

BuzzFeed's description of specific statements to the special counsel's office, and characterisation of documents and testimony obtained by this office, regarding Michael Cohen's congressional testimony are not accurate.

Robert Mueller's spokesman

The report said Mr Cohen then acknowledged Mr Trump’s instructions when he was interviewed by Mr Mueller’s team.

However the special counsel’s spokesman, Peter Carr, said: “BuzzFeed’s description of specific statements to the special counsel’s office, and characterisation of documents and testimony obtained by this office, regarding Michael Cohen’s congressional testimony are not accurate.”

Buzzfeed spokesman Matt Mittenthal said the publication stands by its reporting and to “stay tuned” as they worked to determine what Mr Mueller was denying.

Ben Smith, editor-in-chief of BuzzFeed News, also said the publication stands by its reporting and the sources who informed it.

“We urge the special counsel to make clear what he’s disputing,” Mr Smith said.

Immediately after the special counsel’s statement was issued, Mr Trump retweeted several posts that called the story fake news.

Mr Trump’s lawyer, Rudy Giuliani, tweeted: “I commend Bob Mueller’s office for correcting the BuzzFeed false story that Pres Trump encouraged Cohen to lie.

“I ask the press to take heed that their hysterical desire to destroy this President has gone too far. They pursued this without critical analysis all day. #FAKENEWS.”

The extraordinary statement from Mr Mueller’s office came after Democrats had vowed to investigate whether the report was true, calling that possibility a “concern of the greatest magnitude”.

House intelligence committee Chairman Adam Schiff, a Democratic Representative from California, and House Judiciary Committee Chairman Jerrold Nadler, a Democratic Representative from New York, both said they would investigate BuzzFeed’s account.

Some Democrats even said that if the report were true, then Mr Trump should be impeached.

The Associated Press had not independently confirmed the report.

Any evidence that Mr Trump directed a witness to lie to investigators would place him in the greatest political and legal jeopardy yet.

Mr Giuliani said in a statement earlier on Friday that “any suggestion — from any source — that the President counselled Michael Cohen to lie is categorically false”.

White House spokeswoman Sarah Huckabee Sanders called the allegation “absolutely ridiculous”.

On Twitter on Friday morning, Mr Trump accused Cohen of “lying to reduce his jail time!”

Cohen pleaded guilty in November to lying to Congress to cover up that he was negotiating the Trump Tower project on Mr Trump’s behalf during the heat of his presidential campaign.

The charge was brought by Mr Mueller and was the result of Cohen’s cooperation with that probe.

Cohen admitted that he lied when he told lawmakers he had never agreed to travel to Russia in connection with the Moscow project and when he said that he had decided by the end of January 2016 that the “proposal was not feasible for a variety of business reasons and should not be pursued further”.

He was sentenced to three years in prison for crimes that included arranging the payment of hush money to conceal his boss’ alleged sexual affairs.

He told a judge that he agreed time and again to cover up Mr Trump’s “dirty deeds” out of “blind loyalty”.

Mr Giuliani noted that Mr Cohen had pleaded guilty to lying and quoted federal prosecutors in New York who chastised him for a “pattern of lies and dishonesty over an extended period of time”.

Mr Mueller’s team, however, had previously called him a credible witness.

“Today’s claims are just more made-up lies born of Michael Cohen’s malice and desperation,” Mr Giuliani said.

Lanny Davis, an adviser to Mr Cohen, declined to comment.