Special counsel Robert Mueller's first public statement on the Russia investigation on Wednesday ramped up calls to begin impeachment proceedings against President Donald Trump.
Senators Cory Booker and Kirsten Gillibrand joined fellow Democrats Kamala Harris and Elizabeth Warren in calling for impeachment proceedings, with both Warren and Harris saying that Mueller had delivered an "impeachment referral", The Hill reported.
Gillibrand was quoted as saying that "it's time for Republicans and Democrats to begin impeachment hearings and follow the facts wherever they may lead. We cannot let this president defy basic accountability measures built into our Constitution."
In a statement, she further pointed to the Trump administration's refusal to comply with congressional subpoenas and "the fact that Robert Mueller clearly expects Congress to exercise its constitutional authority and take steps that he could not."
In his statement in the morning, Mueller, who spent nearly two years investigating Russian interference in the 2016 election, and the Trump campaign's and administration's actions in relation to it, reiterated what he had written in the report he completed last month.
"If we had had confidence that the president clearly did not commit a crime, we would have said so," he added.
"We did not, however, make a determination as to whether the president did commit a crime," The New York Times quoted Mueller as saying.
The Justice Department had released Mueller's report in redacted form last month. It detailed several instances of Russian interference in the 2016 presidential election and also laid out 10 instances of potential obstruction. Trump has insisted that he did not obstruct justice or coordinate with Russia.
Before Wednesday's statement, a number of 2020 presidential candidates had already called for impeachment proceedings, with Warren last month becoming the first White House contender to call for impeachment.
"What Robert Mueller basically did was return an impeachment referral. Now it is up to Congress to hold this president accountable," Harris tweeted.
She added, "We need to start impeachment proceedings. It's our constitutional obligation."Meanwhile, Booker said that the Congress "has a legal and moral obligation to begin impeachment proceedings immediately."
"This Administration has continued to stonewall Congress's oversight. Beginning impeachment proceedings is the only path forward," he further stated.
Warren similarly called for congressional action, saying, "Mueller's statement makes clear what those who have read his report know: It is an impeachment referral, and it's up to Congress to act. They should."
In addition, former Representative Beto O'Rourke called impeachment proceedings the only way to ensure "consequences, accountability, and justice."
Speaking about his Russia probe report, Mueller said that Trump could not be charged as he is in office, and charging him would be unconstitutional.
Meanwhile, Trump, who has repeatedly called Mueller's probe as a "witchhunt", said there was "insufficient evidence" and the "case is closed".
"Nothing changes from the Mueller Report. There was insufficient evidence and therefore, in our Country, a person is innocent. The case is closed! Thank you," he said.
( With inputs from ANI )