The Trump administration has buckled and agreed to hand over to Democrats in Congress evidence upon which Robert Mueller prepared his Russia report.

On a day that Democrats on the House judiciary committee were set to hear from former Watergate lawyer John Dean about the report, and a day before they considered whether to pursue attorney general William Barr for contempt, the department of justice announced it would provide the background material on which the special counsel based his 448-page report.

Democrats, led by judiciary committee chairman congressman Jerry Nadler, have for weeks been seeking an unredacted copy of the report and the background material.

Last month, the committee voted to hold Mr Barr, and former White House counsel Don McGahn, in contempt for failing to cooperate and, in the case of Mr Barr, provide the information they requested. The full House had been scheduled to vote on Tuesday on whether to proceed; if the House voted yes, it would authorise a civil lawsuit against the attorney general.

Barely 24 hours before that vote was due to go ahead, the department of justice announced it was providing the materials sought by Democrats, perhaps the first sign that the “maximum pressure” tactics being utilised against Mr Trump may be working. He had previously told the White House to resist all requests for materials or testimony from officials, claiming Democrats were continuing what he termed a “witch hunt”.

Mueller investigation: The key figures Show all 12 1 /12 Mueller investigation: The key figures Mueller investigation: The key figures Robert Mueller is the special counsel overseeing the investigation into Russia's meddling in the 2016 election, and potential obstruction of justice by the president. Mr Mueller has a pristine reputation in Washington, where he was previously in charge of the FBI. Throughout his investigation, he and his team have been notoriously tight lipped about what they know and where their investigation has led. REUTERS Mueller investigation: The key figures Former FBI director James Comey was the catalyst that led to the appointment of special counsel Robert Mueller. Mr Comey was fired by the president after Mr Trump reportedly asked him to drop his own Russia investigation. Mr Trump has long maintained that the investigation is a "witch hunt". AFP/Getty Images Mueller investigation: The key figures Deputy attorney general Rod Rosenstein had authority over the special counsel investigation for much of the two years it has been active. Mr Rosenstein found himself with that responsibility after then-attorney general Jeff Sessions recused himself from that oversight. AP Mueller investigation: The key figures Attorney general Jeff Sessions's decision to recuse himself from oversight of the special counsel investigation may have cost him his job in the end. Mr Sessions resigned last year, after weathering a contentious relationship with Donald Trump who vocally criticised his attorney general for taking a step back. Mr Sessions recused himself from the oversight citing longstanding Justice Department rules to not be involved in investigations overseeing campaigns that officials were apart of. AP Mueller investigation: The key figures Attorney General William Barr is currently responsible for oversight of the special counsel investigation. Mr Barr's office will be the first to receive the Mueller report when it is finished. His office will then determine what portion or version of that report should be delivered to Congress, and also made public. EPA Mueller investigation: The key figures Michal Cohn is the president's former personal lawyer, who has been helping the special counsel investigation as a part of a plea deal over financial crimes, and campaign finance crimes, he has pleaded guilty to. Among those crimes, Cohen admitted to facilitating $130,000 in hush money payments to adult film actress Stormy Daniels during the 2016 campaign. Cohen has said he did so at the direction of Mr Trump. Cohen has also admitted that he maintained contacts with Russian officials about a potential Trump real estate project in Moscow for months longer than Mr Trump and others admitted. The talks continued well into 2016 during the campaign, he has said. AP Mueller investigation: The key figures Stormy Daniels has alleged that she had an affair with Donald Trump in 2006, soon after Melania Trump gave birth to Baron Trump. The accusation is of particular importance as a result of the $130,000 hush money payment she received to keep quiet about the affair during the 2016 campaign. AP Mueller investigation: The key figures Paul Manafort was Donald Trump's former campaign chairman. Manafort was charged alongside Rick Gates for a slew of financial crimes, and was convicted on several counts in a Virginia court. He then pleaded guilty to separate charges filed in a Washington court. Manafort has been sentenced to just 7.5 years in prison for his crimes — in spite of recommendations from the special counsel's office for a much harsher sentence. AP Mueller investigation: The key figures George Papadopoulos was one of the first individuals associated with the Trump campaign to be charged by the Mueller probe. He ultimately received a 14 day prison sentence for lying to investigators about contacts he had with Russian officials. AP Mueller investigation: The key figures Roger Stone is a well known political fixer and operative, who has made a name for himself for some dirty tactics. He has been charged by the Mueller probe earlier this year, and he has been said to have had prior knowledge that WikiLeaks planned on publishing stolen emails from the Hillary Clinton campaign in 2016. Getty Images Mueller investigation: The key figures Rick Gates was charged alongside former Trump campaign chairman Paul Manafort for a range of crimes. Gates, who worked alongside Manafort for a pro-Russia Ukrainian political party. The two were charged with conspiracy and financial crimes. Gates pleaded guilty. AP Mueller investigation: The key figures Former national security adviser Michael Flynn was one of the first casualties of the Russia scandal, and was forced out of his position in the White House weeks after Donald Trump took office. Flynn pleaded guilty in 2017 to "willfully" making fraudulent statements about contacts he had with Russian officials including former Russian ambassador to the US Sergey Kislyak. Flynn then lied to Vice President Mike Pence about that contact. REUTERS

It was not immediately clear how much material the department had agreed to hand over, following weeks of tense sparring between the administration and senior Democrats.

But Democrats said they were for now suspending plans to press ahead with a contempt vote.

“I am pleased to announce the department of justice has agreed to begin complying with our committee’s subpoena by opening Robert Mueller’s most important files to us, providing us with key evidence that the special counsel used to assess whether the president and others obstructed justice or were engaged in other misconduct,” Mr Nadler said in a statement.

Trump speaks to press following Mueller resignation: "Russia did not help me get elected. You know who got me elected - I got me elected"

“It is critical that congress is able to obtain the information we need to do our jobs, ensuring no one is above the law and bringing the American public the transparency they deserve.”

The New York Times pointed out that although the Democrats had pulled back from their threat to vote on whether to file a lawsuit against Mr Barr, they still intended to vote to authorise Mr Nadler’s committee to go to court to seek full enforcement of its subpoena “and to petition a judge to unseal grand jury secrets”.

“If the Department proceeds in good faith and we are able to obtain everything that we need, then there will be no need to take further steps,” added Mr Nadler, who reportedly wishes to push for the impeachment of Mr Trump but is being held back by House speaker Nancy Pelosi.

“If important information is held back, then we will have no choice but to enforce our subpoena in court and consider other remedies.”

Mr Mueller’s 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.