President Trump called on his violent supporters to go home, but repeated false claims the election had been stolen which many said helped to incite further violence.
In the wake of the attack, millions of people called for his removal from office.
US Congressman Ted Lieu tweeted: “He is why the 25th amendment exists when the president has ‘lost it.’ If Trump doesn’t resign, then [vice president] Mike Pence needs to start the process to remove [Donald Trump] ASAP.”
Mr Lieu later tweeted: “Leadership in the Senate and House are misreading the situation if they simply adjourn after we accept the electoral college results. There is much anger among the members and the American public. We cannot just leave without holding Trump accountable. That will only embolden him.”
In a statement after the attack, the Assistant House Speaker Katherine Clark said: “Despite the seditious attempt to overthrow our democracy, we in Congress will fulfil our duty to ensure the will of the people and the integrity of our democracy are upheld.
“But the next days and weeks remain dangerous. Donald Trump is a traitor to our country and our Constitution. He must be removed from office and prevented from further endangering our country and our people.”