Trump claims victory in wake of Mueller testimony

US President Donald Trump declared the Russia meddling and obstruction probe a "big hoax" Wednesday as Democrats reaped precious little new ammunition for impeachment in marathon testimony to Congress by investigation leader Robert Mueller.

Mueller said during his hotly-anticipated appearance that he had not exonerated Trump of obstruction allegations, but once again declined to accuse the US president of a crime or recommend that Congress do so.

Answering questions on his investigation for the first time, a shaky-voiced, sometimes uncertain Mueller would not go beyond the facts set out in his final investigation report and refused dozens of times to answer questions from both Democrats and Republicans.

Mueller's report, made public in April, outlined a pattern of attempted cooperation between Trump's 2016 campaign and Russia which didn't rise to the level of a criminal conspiracy -- and at least 10 instances of alleged interference in the probe by Trump.

But the former FBI director denied Democrats seeking an impeachment effort their number one goal, an unequivocal statement on national television that Trump had criminally obstructed justice.

Republicans quickly declared the Russia investigation over and Trump said it was "a very big day" for himself and the country.

"This whole thing has been three years of embarrassment and a waste of time for our country," he told reporters. "The Democrats lost so big today," he added.

The marathon day of nationally-televised hearings did little to resolve the outcome of Mueller's 22-month investigation, which outraged and at times shook the White House, as indictments came down for six former Trump aids and associates, five of whom were convicted.

Mueller explained that he could not have charged Trump because Justice Department rules prohibited him from indicting a sitting president. And he later added that Trump could theoretically be indicted after he leaves office.

But beyond that, the 74-year-old veteran prosecutor had little to add, failing to clear up the confusion left among the American public about the conclusions of his dense report.

He answered many questions by directing lawmakers to the document, while at times appearing to forget or to be unfamiliar with details contained within.

The Democrats, who declined last week to advance an impeachment motion launched from within their own ranks, said Mueller's testimony added to arguments for removing the president and that they would continue to seek information that could advance the case.