"We’re going to go down one track at a time,"he said,echoing a threat he first made in this year's State of the Union address.

At a later press conference,Pelosi said Democrats were prepared to work with Trump to deliver a major infrastructure package to help repair the nation's roads,bridges and airports.

"He just took a pass,and it just makes me wonder why he did,"Pelosi said."In any event,I pray for the President of the United States,and I pray for the United States of America."

Democratic Senate leader Charles Schumer said:"To watch what happened in the White House would make your jaw drop."

Pressure to launch impeachment proceedings is growing in the Democratic caucus,even though Pelosi has warned her colleagues not to move too quickly.

Congressional Democrats have been growing increasingly frustrated about the White House's refusal to comply with subpoenas for documents and witnesses.

Trump has so far blocked access to his tax returns and declined to make witnesses such as former White House counsel Don McGahn available to testify before Congress about special counsel Robert Mueller's investigation into Russian election meddling.

Democrats have also been unable to secure an appearance by Mueller himself.

"The President’s refusal to produce evidence or permit witness testimony defies not only the rule of law but the basic protections of our constitution,"Democratic congresswoman Mary Gay Scanlon said this week.

"The time has come to start an impeachment inquiry because the American people deserve to know the truth and to have the opportunity to judge the gravity of the evidence and charges levelled against the President."

Trump's threat to boycott any co-operation with Democrats further lowers the bar for impeachment as it is already clear that bipartisan legislation has little chance of success.

Some Democrats even believe Trump is trying to goad them into impeachment as he knows it is unpopular with the American people and would galvanise support among his base.

Meanwhile on Wednesday a federal judge in Manhattan ruled against a Trump request to block Deutsche Bank from supplying his financial records,while New York legislators approved a bill that would allow Congress to obtain Trump's state tax returns. The decisions come on top of a judge in Washington overruling Trump's request to block his accounting firm from divulging records on Monday.