Photo: The Canadian Press

Special counsel Robert Mueller found no evidence President Donald Trump's campaign "conspired or co-ordinated" with Russia to influence the 2016 presidential election but reached no conclusion on whether Trump obstructed justice. That brought a hearty claim of vindication from Trump but set the stage for new rounds of political and legal fighting.

The battle began Monday as White House aides and allies blanketed television news broadcasts to trumpet the findings and claim that Trump has been the victim in a probe that never should have started.

White House spokeswoman Sarah Sanders said Trump will let Attorney General William Barr decide whether the special counsel's Russia report should be publicly released, though she adds that "he's more than happy for any of this stuff to come out."

Trump cheered the Sunday outcome but also laid bare his resentment after two years of investigations that have shadowed his administration. "It's a shame that our country has had to go through this. To be honest, it's a shame that your president has had to go through this," he said.

Democrats pointed out that Mueller found evidence for and against obstruction and demanded to see his full report. They insisted that even the summary by the president's attorney general hardly put him in the clear.

Mueller's conclusions, summarized by Barr in a four page letter to Congress, represented a victory for Trump on a key question that has hung over his presidency from the start — whether his campaign worked with Russia to defeat Democrat Hillary Clinton.

That was further good news for the president on top of the Justice Department's earlier announcement that Mueller had wrapped his investigation without new indictments. That could deflate the hopes of Democrats in Congress and on the 2020 campaign trail that incriminating findings from Mueller would hobble the president's agenda and re-election bid.

But while Mueller was categorical in ruling out criminal collusion, he was more circumspect on presidential obstruction of justice. Despite Trump's claim of total exoneration, Mueller did not draw a conclusion one way or the other on whether he sought to stifle the Russia investigation through his actions including the firing of former FBI director James Comey.

According to Barr's summary, Mueller set out "evidence on both sides of the question" and stated that "while this report does not conclude the president committed a crime, it also does not exonerate him."

Barr, who was nominated by Trump in December, and Deputy Attorney General Rod Rosenstein, who appointed Mueller in May 2017 and oversaw much of his work, went further in Trump's favour.

The attorney general said he and Rosenstein had determined that Mueller's evidence was insufficient to prove in court that Trump had committed obstruction of justice to hamper the probe. Barr has previously voiced a broad view of presidential powers, and in an unsolicited memo last June he cast doubt on whether the president could have obstructed justice through acts — like firing his FBI director — that he was legally empowered to take.

Barr said their decision was based on the evidence uncovered by Mueller and not affected by Justice Department legal opinions that say a sitting president cannot be indicted.

Mueller's team examined a series of actions by the president in the last two years to determine if he intended obstruction. Those include his firing of Comey one week before Mueller's appointment, his public and private haranguing of then-Attorney General Jeff Sessions for recusing himself from the Russia investigation because of his work on the campaign, his request of Comey to end an investigation into Michael Flynn, the White House's first national security adviser, and his drafting of an incomplete explanation about his oldest son's meeting with a Russian lawyer during the campaign.

Mueller's findings absolve Trump on the question of colluding with Russia but don't entirely remove the legal threats the president and associates are facing. Federal prosecutors in New York, for instance, are investigating hush-money payments made to two women during the campaign who say they had sex with the president. Trump's former personal lawyer, Michael Cohen, implicated Trump in campaign finance violations when he pleaded guilty last year.