White House may seek to prevent McGahn from complying with House subpoena

A source familiar with the discussion said the White House could assert executive privilege over specific aspects if McGahn testifies, but noted that discussions are not that far along yet and added that other measures are still being considered.

Sources familiar with the matter said that the House Judiciary Committee has had discussions with McGahn's attorney, William Burck, but has not been told yet whether McGahn will comply with the subpoena, which requests documents by May 7 and his testimony by May 21. Burck did not respond to a request for comment.

Before the subpoena was issued, McGahn's attorney sent a letter to the House Judiciary Committee stating that they need to ask the White House for documents, not his client, according to a person familiar with the letter. He also told lawmakers that any documents related to the campaign would have to come from the campaign lawyers, this person said.

This comes as the White House is escalating its efforts to push back against congressional inquiries that they argue cross the line.

On Monday, the White House instructed former security director Carl Kline not to show up for a scheduled deposition on security clearances because House Oversight Chairman Elijah Cummings refused to allow a White House attorney to be present. And the White House will likely instruct John Gore, a top Justice Department official, not to show up for scheduled testimony if he cannot have a Justice Department lawyer present, an official told CNN.

Democrats want to question Gore about the decision to add a citizenship question to the 2020 Census. Gore met with the committee back in March, but Cummings said he refused to answer multiple questions by citing ongoing litigation.