US President Donald Trump and his lawyers will not attend an impeachment hearing this week because it lacks "fundamental fairness", the White House has said.
Rejecting the call to face the Democrat-led congressional investigation on Wednesday, presidential counsel Pat Cipollone lambasted the baseless and highly partisan inquiry.
In a letter to Jerrold Nadler, the chairman of the House Judiciary Committee, Mr Cipollone accused him of no doubt purposely scheduling the hearing when he knew Mr Trump would be attending a NATO summit in London.
Mr Cipollone wrote: As you know, this baseless and highly partisan inquiry violates all past historical precedent, basic due process rights, and fundamental fairness.
He added: We cannot fairly be expected to participate in a hearing while the witnesses are yet to be named and while it remains unclear whether the Judiciary Committee will afford the president a fair process through additional hearings.
Mr Cipollone also highlighted the complete lack of due process and fundamental fairness afforded the president throughout this purported impeachment inquiry.
It would have been the first direct involvement by the White House in a process that Mr Trump has condemned as a partisan witch hunt.
Responding to the White House letter, Democratic US Representative Don Beyer tweeted: Not one process complaint made by the president and his Republican allies in Congress so far has turned out to be genuine.
Congressional investigators have been looking into whether Mr Trump abused his power by pressuring Ukraine to launch investigations into former Democratic vice president Joe Biden, who is running to unseat him in the 2020 presidential race, and a discredited conspiracy theory that Ukraine, not Russia, interfered in the 2016 election.
The planned hearings represent a further step toward possible charges being brought.
Democratic House Speaker Nancy Pelosi, who will make the final decision, has not yet said whether the Republican president should be impeached.
But in a letter to supporters last week, she called for him to be held accountable for his actions.
Mr Trump has denied any wrongdoing, dismissing the impeachment inquiry as a sham.
Mr Nadler has also set a second deadline on Friday for Mr Trump to say whether he or his legal team would participate in further proceedings expected next week to examine evidence against him.
We may consider participating in future Judiciary Committee proceedings if you afford the administration the ability to do so meaningfully, Mr Cipollone wrote, laying out a list of demands, including allowing Republicans to call additional witnesses.
The committee could vote on whether to recommend impeachment within the next two weeks, setting the stage for a possible vote by the full House before Christmas, according to Democratic aides.
If the House impeaches Mr Trump, the Republican-controlled Senate would hold a trial to decide whether he should be removed from office.
However, Senate Republicans have shown no sign of wanting to ditch Mr Trump.