Special counsel Robert Mueller's report on Russian meddling in the 2016 election did not find enough evidence that Trump campaign officials knowingly conspired with Moscow, according to details released on Sunday. Attorney General William Barr sent a summary of conclusions from the report to congressional leaders on Sunday afternoon. Mr Mueller concluded his investigation on Friday after nearly two years and delivered his report to Mr Barr. The summary said the special counsel’s team did not find sufficient evidence to establish that the president illegally obstructed justice, but Mr Mueller's team stopped short of exonerating Mr Trump. In the investigation, Mr Mueller issued more than 2,800 subpoenas, nearly 500 search warrants, obtained more than 230 orders for communications records and interviewed about 500 witnesses. Responding to the report while boarding Air Force One to Washington, Mr Trump said it was "an illegal take-down that failed". He said it was "complete exoneration, no collusion, no obstruction". "It's a shame our country had to go through this and, to be honest, it's a shame that our president had to go through this before the election," Mr Trump said. The report will be read by his supporters as clearing him of the two major allegations that have hung over his presidency – collusion and obstruction of justice. But the Democrats in Congress seem certain to assert their right to determine the president’s guilt or innocence over obstruction of justice. "We noted that the special counsel recognised that the evidence does not establish that the president was involved in any underlying crime related to Russian election interference," Mr Barr said in his summary. The White House was not involved in any review or discussion of the Mueller report and did not look at Mr Barr's summary ahead of time, a Justice Department official told <em>Bloomberg.</em> The report said that Mr Trump's 2016 election campaign during the election did not point to obstruction of justice, but it outlined Russia's efforts to influence the the presidential election. The investigation did not find that the Trump campaign or anyone associated with it conspired or co-ordinated with Russia in efforts to influence the election. “The special counsel did not find any collusion and did not find any obstruction,” White House press secretary Sarah Sanders said. “Attorney General Barr and Deputy Attorney General Rosenstein further determined there was no obstruction. The findings of the Department of Justice are a total and complete exoneration of the president of the United States.” Mr Trump, who was at his Mar-a-Lago resort for the weekend, remained uncharacteristically silent about the end of the investigation. He has frequently derided Mr Mueller's work as a "witch hunt" and denies collaborating with Moscow or obstructing justice. Russia says it did not interfere in the election. Democrats are likely to seize on the fact that the summary does not exonerate the president. Mr Barr is under no obligation to release the report publicly but he said it was his goal to release as much of it as he could.