The U.S. House of Representatives Judiciary Committee on Tuesday invited President Donald Trump to its first impeachment hearing, scheduled for December 4, starting the next phase in a process that could lead to formal charges against the president.

The hearing, scheduled for 10 a.m. EST (1500 GMT), will have legal experts as witnesses, Reuters said. They have not yet been identified.

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A House Democratic aide declined to comment on whether the Judiciary Committee expected to receive a formal report on the Intelligence Committee-led investigation into the Trump administration's dealings with Ukraine before the hearing.

Representative Jerrold Nadler, the Democratic chairman of the committee, said in a statement that he had written to Trump to remind him that the committee's rules allow the president to attend the hearing, and for his counsel to question the witnesses. "At base, the president has a choice to make: He can take this opportunity to be represented in the impeachment hearings, or he can stop complaining about the process. I hope that he chooses to participate in the inquiry, directly or through counsel, as other presidents have done before him."

Nadler said in his letter that the hearing was intended as an opportunity to discuss the historical and constitutional basis of impeachment, as well as the meaning of terms like "high crimes and misdemeanors."