Pence’s decision comes less than a month after Trump hired his own private attorney, Marc E. Kasowitz, to help navigate the investigations related to the Russia probe, and a day after the Washington Post reported that special counsel Robert S. Mueller III is now widening his investigation to examine whether the president attempted to obstruct justice.

“I can confirm that the Vice President has retained Richard Cullen of McGuire Woods to assist him in responding to inquiries by the special counsel,” said Jarrod Agen, a Pence spokesman, in an email statement. “The Vice President is focused entirely on his duties and promoting the President’s agenda and looks forward to a swift conclusion of this matter.”

Cullen will not be paid with taxpayer funds, an aide said. Cullen referred questions to the vice president’s office.