Democrats are calling a witness from the Watergate era as they prepare for a hearing on Robert Mueller’s Russia report, the latest attempt to intensify pressure on Donald Trump.

Politicians on Capitol Hill had hoped both Mr Mueller and former White House counsel Don McGahn would give testimony before the House judiciary committee.

But because the two men have declined to appear, Democrats will instead question John Dean, 80, who served as counsel to Richard Nixon, and who served time in jail for his role as a major orchestrator of Watergate scandal cover-up.

“These hearings will allow us to examine the findings laid out in Mueller’s report so that we can work to protect the rule of law and protect future elections through consideration of legislative and other remedies,” declared committee chairman Jerry Nadler, who is said to want to launch impeachment proceedings against the president.

“Given the threat posed by the president’s alleged misconduct, our first hearing will focus on Mr Trump’s most overt acts of obstruction. In the coming weeks, other hearings will focus on other important aspects of the Mueller report.”

The decision to call Dean appears to be attempt to directly jab at Mr Trump, who has told the White House to push back at all requests by Democrats for his aides and officials to testify.

Dean, who in 1973 pleaded guilty to one count of obstruction of justice and who testified about the Nixon-orchestrated burglary at the Democratic National Committee headquarters at the Watergate building in Washington DC, has long been an outspoken critic of the president.

Last year, he said Mr Trump’s presidency had made the “long nightmare of Watergate seem like a brief idyllic daydream”.

“History will treat Nixon’s moral failures as relatively less troubling than Trump’s sustained and growing decadence, deviousness and self-delusive behaviour,” he tweeted. “Nixon = corrupt; Trump = evil.”

Monday’s hearing is one of several events during which Democrats will seek to turn the screw on Mr Trump, according to the Associated Press.

Story continues

On Tuesday, the House of Representatives will vote on whether to authorise contempt cases against attorney general William Barr and Mr McGahn for failing to comply with subpoenas.

On Wednesday, the House intelligence committee will examine the counterintelligence implications of Russia’s alleged interference in the 2016 election.

Mr Mueller’ two-year probe of Russia’s actions and possible collusion with the Trump campaign, found no evidence of a conspiracy between Moscow and members of the president’s team.

On the question of obstruction of justice, Mr Mueller said the team was unable to exonerate the president and that prosecutors were unable – because of longstanding department of justice guidelines – to consider indicting a sitting president.

Would someone get Trump a dog. He needs a friend so he won’t endlessly vent on Twitter. He’s uninterested in government and policy. He doesn’t read. He doesn’t exercise. He has no real friends. A dog might save humankind. Admittedly, it a lot to ask of a dog. But help is needed. — John Dean (@JohnWDean) June 9, 2019

Mr Barr and his then deputy Rod Rosenstein, decided there was insufficient evidence to charge Mr Trump.

The president has repeatedly denounced the probe as a witch hunt.