A second Republican US senator called for President Donald Trump to resign on Sunday, saying he could face criminal liability after the deadly storming of the Capitol by his supporters.

The remarks by Senator Pat Toomey, a conservative supporter of Trump until recently, came as Democrats in the US House of Representatives prepared to move forward with impeachment proceedings and amid federal investigations of Wednesday’s assault on the seat of government.

Republican Trump, who has falsely contested the validity of Democrat Joe Biden’s presidential victory, praised and egged on his supporters before they laid siege to the Capitol, where lawmakers were certifying the Electoral College vote for Biden.

“I think the best way for our country is for the President to resign and go away as soon as possible,”

Toomey said on NBC’s “Meet the Press,” calling Trump’s behaviour since the election “outrageous”.

Toomey, appearing on Sunday television news shows, said he did not think there was time for impeachment with only 10 days left in Trump’s term, and noted there did not appear to be consensus to use the Constitution’s 25th Amendment to strip Trump of his powers.

He told CNN he believed Trump could be held criminally liable in the events at the Capitol.

Lisa Murkowski on Friday became the first Republican US senator to say Trump should resign immediately.