Gov. Roy Cooper of North Carolina, who has been seen as a leading contender to become Vice President Kamala Harris’s running mate, has informed her team that he has withdrawn from the vice-presidential sweepstakes, according to two people briefed on the matter.

Mr. Cooper, who previously served as chairman of the Democratic Governors Association, was believed to be among the half-dozen top candidates to join Ms. Harris on the Democratic ticket.

It was not immediately clear why he had taken himself out of consideration. A spokesman for the Harris campaign declined to comment, as did a spokesman for Mr. Cooper.

Mr. Cooper has known Ms. Harris dating to their overlapping days as state attorneys general and also campaigned recently with her. He has twice won governor’s races in North Carolina, a battleground state, even as Donald J. Trump carried the state at the presidential level. Mr. Cooper is prohibited from seeking a third term.

Mr. Cooper, 67, is older than Ms. Harris, 59, but still a decade younger than Mr. Trump.

Ms. Harris is seeking to select a running mate on a highly compressed timeline, aiming to make her choice by Aug. 7 — a little more than two weeks after she entered the race to replace President Biden on the Democratic ticket.

Besides Mr. Cooper, those known to be under serious consideration include Gov. Josh Shapiro of Pennsylvania, Gov. Tim Walz of Minnesota, Gov. Andy Beshear of Kentucky, Senator Mark Kelly of Arizona and the transportation secretary, Pete Buttigieg.