Former Special Prosecutor Robert Mueller on Wednesday said United States President Donald Trump had not been exonerated for obstructing his investigations into Russia’s attempts to help Trump win the 2016 presidential elections, AP reported.

“The president was not exculpated for the acts that he allegedly committed,” said Mueller at the first of two back-to-back congressional hearings into his inquiry. He also described the Russian government’s efforts to intervene in politics of the United States as one of the most serious challenges to democracy.

“Obstruction of justice strikes at the core of the government’s efforts to find the truth and to hold wrongdoers accountable,” Reuters quoted the former special counsel as saying. Trump had, earlier in March, claimed that the Mueller investigations had led to “complete and total exoneration” of the president.

House of Representatives Judiciary Committee chairman Jerrold Nadler on Wednesday asked Muller if Trump was correct in repeatedly claiming that the report had “found that there was no obstruction and that it completely and totally exonerated him”, to which Mueller responded saying, “That is not what the report said”.

Mueller also said that he would not answer questions pertaining to the origins of the Russia investigations in the Federal Bureau of Investigation before he was asked to take over in 2017. He also added that he would speak about a controversial dossier put together by a former British intelligence agent.

“Your investigation actually found quote ‘multiple acts by the president that were capable of exerting undue influence over law enforcement investigations, including the Russian interference and obstruction of investigations.’ Is that correct?” CNBC quoted Nadler as saying, to which Mueller responded with: “Correct”.

Early on Wednesday, the United States president criticised the Democrats before the congressional hearings. “So Democrats and others can illegally fabricate a crime, try pinning it on a very innocent President, and when he fights back against this illegal and treasonous attack on our Country, they call It Obstruction? Wrong!” he tweeted. “Why didn’t Robert Mueller investigate the investigators?”

In March, United States Attorney General William Barr had announced that the investigation led by Mueller had found that Trump’s campaign in 2016 did not collude with the Russian government. The report, however, said that “while this report does not conclude that the president committed a crime, it also does not exonerate him.”