Mike Pence has hired McGuireWoods' Richard Cullen as outside legal counsel to handle inquiries related to the special counsel investigation into Russian efforts to interfere with the 2016 election, NBC News has confirmed.

Pence will not be using taxpayer dollars to pay Cullen, a person close to the vice president told NBC.

Cullen referred questions to Pence's office.

The Washington Post first reported Cullen's hiring.

Cullen previously served as attorney general of Virginia. He was also appointed as U.S. attorney for the Eastern District of Virginia under President George H.W. Bush.

Pence's hiring of Cullen comes after President Donald Trump retained Marc Kasowitz in May as his own counsel to deal with matters related to the Russia investigation.

According to reports, special counsel Robert Mueller has expanded the scope of the investigation to include whether the president obstructed justice. The investigation is also looking into whether the Trump campaign colluded with Moscow.

— NBC News contributed reporting.

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