Washington plunged into an impeachment crisis on Wednesday, as House Democrats opened an investigation into President Donald Trump’s campaign season dealings with Ukraine. Trump repeatedly prodded Ukraine’s president to look into Democratic rival Joe Biden, according to a rough transcript released by the White House.

“Whatever you can do with the attorney general would be great,” Trump said in the summer phone call. He was referring to Attorney General William Barr, the nation’s top law enforcement official.

The president’s words set the parameters of the political debate to come, with Trump dismissing it as routine and Democrats saying that it laid the predicate for an impeachment inquiry.

The release came against the backdrop of Trump’s meetings with world leaders at the United Nations, a remarkable split screen even for the turbulence of the Trump era. On Trump’s schedule Wednesday: a meeting with Ukrainian President Volodymyr Zelenskiy, whose contacts with Trump are now central to the impeachment inquiry.

House Speaker Nancy Pelosi launched the formal impeachment inquiry on Tuesday, yielding to mounting pressure from fellow Democrats and plunging a deeply divided nation into an election year clash between Congress and the commander in chief. The probe injects deep uncertainty into the 2020 election campaign and tests anew the nation’s constitutional system of checks and balances.

Trump, who thrives on combat, has all but dared Democrats to take this step, confident that the specter of impeachment led by the opposition party will bolster rather than diminish his political support.

“There has been no President in the history of our Country who has been treated so badly as I have,” he tweeted Wednesday from New York. “The Democrats are frozen with hatred and fear. They get nothing done. This should never be allowed to happen to another “President. Witch Hunt!

While Pelosi’s announcement adds weight to the work being done on the oversight committees, the next steps are likely to resemble the past several months of hearings and legal battles — except with the possibility of actual impeachment votes.

On Wednesday, the Democratic-controlled House is expected to consider a symbolic but still notable resolution insisting the Trump administration turn over to Congress the whistleblower’s complaint. The Republican-led Senate, in a rare bipartisan moment, unanimously approved a similar resolution Tuesday.

The lawyer for the whistleblower, who is still anonymous, released a statement saying he had asked Trump’s director of national intelligence to turn over the complaint to House committees and asking guidance to permit the whistleblower to meet with lawmakers.