UPDATE 1-White House's Mulvaney to sue over House impeachment subpoenas

Acting White House Chief of Staff Mick Mulvaney on Monday withdrew his request to join a lawsuit seeking a court ruling on whether witnesses must testify in the U.S. House of Representatives impeachment inquiry into President Donald Trump, saying he would instead file his own case, according to a court document. Mulvaney had earlier sought to participate in a lawsuit filed by Charles Kupperman, a former deputy to ousted national security adviser John Bolton, seeking a court ruling on whether he should comply with a congressional subpoena or honor the Trump administration's order not to testify.

Mulvaney withdrew that request following a conference call held by the judge assigned to Kupperman's lawsuit.