(The Hill) – The House committee investigating the Jan. 6 attack on the Capitol took the remarkable step Wednesday of asking for voluntary cooperation from House Minority Leader Kevin McCarthy (Calif.), the highest-ranking Republican to face such a request in the probe.

In a six-page letter to McCarthy, the committee laid out a host of questions for the Republican leader who initially condemned the attack and President Trump’s role in it but who has since become a chief critic of the panel and its work.

“You have acknowledged speaking directly with the former President while the violence was underway on Jan. 6….Further, you shared an account of your communications with President Trump with a local news outlet in your district, which reported that you had a ‘very heated conversation’ with the President as the riot was taking place, and urged the President to ‘get help’ to the Capitol,” Chair Bennie Thompson (D-Miss.) wrote in the letter to McCarthy.

“As is readily apparent, all of this information bears directly on President Trump’s state of mind during the January 6th attack as the violence was underway.”

The committee asks to meet with McCarthy as soon as Feb. 3, requesting he divulge information about his communications with Trump “before, during and after the violent Jan. 6 attack.”

The letter dissects McCarthy’s response to the attack, starting with his speech on the House floor where he said Trump “bears responsibility” for the attack.

It then uses multiple sources to relay McCarthy’s intense exchange with the White House during the attack and how he encouraged Trump to call off his supporters.

But the committee argues McCarthy’s tone changed following a meeting with Trump at Mar-a-Lago organized after the former president made harsh statements about the minority leader.

“Your public statements regarding January 6th have changed markedly since you met with Trump. At that meeting, or at any other time, did President Trump or his representatives discuss or suggest what you should say publicly, during the impeachment trial (if called as a witness), or in any later investigation about your conversations with him on January 6th?” the committee asks.

Just before 6 p.m. on Wednesday McCarthy said he will not participate in the interview with the committee and issued the following statement:

“This committee is not conducting a legitimate investigation as Speaker Pelosi took the unprecedented action of rejecting the Republican members I named to serve on the committee. It is not serving any legislative purpose. The committee’s only objective is to attempt to damage its political opponents – acting like the Democrat Congressional Campaign Committee one day and the DOJ the next. 

“The committee has demanded testimony from staffers who applied for First Amendment permits. It has subpoenaed the call records of private citizens and their financial records from banks while demanding secrecy not supported by law. It has lied about the contents of documents it has received. It has held individuals in contempt of Congress for exercising their Constitutional right to avail themselves of judicial proceedings. And now it wants to interview me about public statements that have been shared with the world, and private conversations not remotely related to the violence that unfolded at the Capitol. I have nothing else to add.

“As a representative and the leader of the minority party, it is with neither regret nor satisfaction that I have concluded to not participate with this select committee’s abuse of power that stains this institution today and will harm it going forward.”

This is a developing story, check back for updates.