Special counsel Robert Mueller did not find evidence that President Trump's campaign conspired with Russia to influence the 2016 election, according to a summary of findings submitted to Congress by Attorney General William Barr.

"The Special Counsel's investigation did not find that the Trump campaign or anyone associated with it conspired or coordinated with Russia in its efforts to influence the 2016 U.S. presidential election," Barr wrote in a letter to leaders of the House and Senate judiciary committees on Sunday afternoon.

That was despite "multiple offers from Russian-affiliated individuals to assist the Trump campaign," he wrote.

However, Mueller's investigation did not take a position on whether Trump obstructed justice by trying to frustrate the ongoing investigation.

"[W]hile this report does not conclude that the President committed a crime, it also does not exonerate him," Barr quotes from Mueller's report.

The attorney general wrote that he and Deputy Attorney General Rod Rosenstein had concluded that the findings of the special counsel were "not sufficient to establish that the president committed an obstruction-of-justice offense."