Robert Mueller disputes accuracy of explosive report on Donald Trump and Michael Cohen

The office of the special counsel has held its tongue since it was established two years ago to investigate allegations of collusion between Donald Trump's campaign and Russia.

It has declined to comment as senior figures were convicted and sentenced. It kept silent as conspiracy theories riddled the media amid lurid allegations of hotel-room escapades in Moscow. And it offered a terse "no comment" to every inquiry about whether Mr Trump's election campaign was in cahoots with Vladimir Putin.

Until now.

On Friday, a two-line email arrived in journalists’ inboxes from Peter Carr, Robert Mueller’s almost Trappist-like spokesman, undermining a sensational story published hours earlier claiming President Trump told his personal attorney Michael Cohen to lie to Congress.

“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,” it said.

If the BuzzFeed story was received like a bombshell – it claimed that Mr Trump had directly attempted to obstruct justice, renewing calls for impeachment among Democrats – the unprecedented nature of the rebuttal made an even bigger splash, sending Mr Trump into Twitter spasms as he retweeted supporters and decried fake news.

“Remember it was Buzzfeed that released the totally discredited ‘Dossier,’ paid for by Crooked Hillary Clinton and the Democrats (as opposition research), on which the entire Russian probe is based,” he wrote, denouncing an unverified intelligence report that the news site published. “A very sad day for journalism, but a great day for our Country!”

The episode has Mueller watchers scratching their heads. After more than 18 months of press speculation and front-page headlines, why issue a statement now? Was it an effort to quiet the runaway calls for impeachment or to rein in expectations that his final report will prove damning to the president?

Joshua Dressler, professor of Law at Ohio State University, said it was difficult to read the intentions of an office that had commented so rarely.

“My own sense is that Mueller may have been concerned that the news story might be interpreted as having come from leaks from his people, so he wanted to demonstrate that it didn’t, by saying there were inaccuracies,” he said.

At the same time, he added, the statement did not completely demolish the BuzzFeed story.

“It is noteworthy, I think, that their statement was very carefully drafted,” he said. “The fact that there were inaccuracies does not tell us whether the essential claim is false. We simply don't know.”

The latest Russia investigation whirlwind began when BuzzFeed published a story on Thursday alleging that Mr Cohen, the president’s long-time legal fixer, had been told by Mr Trump to lie to Congress about negotiations to build a Trump Tower in Moscow. The story cited two federal law enforcement officials.

“It is the first known example of Trump explicitly telling a subordinate to lie directly about his own dealings with Russia,” said the story.

Mr Cohen has already been sentenced to 36 months in prison after pleading guilty to lying but said he had done it out of "blind loyalty" to Mr Trump rather than because he was told to do so.

If the new allegations are true, it could support a case that the president obstructed justice.

The White House denied the claims as “categorically false”. That was followed by the special counsel’s statement.

However, Ben Smith, the editor-in-chief of BuzzFeed, said: “We stand by our reporting and the sources who informed it, and we urge the special counsel to make clear what he’s disputing.”

That it is disputing anything at all is highly unusual. The office has broken its public silence on only three previous occasions.

Last April it offered a general warning to journalists to look out for inaccuracies and be careful about following up other news organisations apparent scoops. In October, it said it had referred a possible smear attempt to the FBI after reporters were offered potentially compromising material on Mr Mueller. And on another occasion it announced that the investigation was drawing to a close.

Matt Miller, a former Department of Justice spokesman, said the gravity of the BuzzFeed allegations, the growing calls for impeachment and the suspicion that the story was based on leaks would have prompted stronger action this time.

“This is without a doubt not the first story about Mueller’s work that has been wrong and usually the special counsel’s office just lets those pass without correcting the public record,” he told MSNBC.

“But I think the difference here was the magnitude of the accusation contained in this story, that the president committed a crime and that they had evidence he committed a crime.”

Mr Mueller’s probe has already led to charges against more than two dozen Russians, as well as several members of Mr Trump’s campaign team, including Michael Flynn, his former national security adviser, and Paul Manafort, the former chairman of his election campaign.

Although there have been signs that the investigation is drawing to a close, it is unclear when its findings will be submitted to the attorney general.