Republican Senator Judd Gregg of New Hampshire abruptly withdrew his nomination as commerce secretary Thursday, citing "irresolvable conflicts" with President Barack Obama's handling of the economic stimulus and 2010 census.

"We are functioning from a different set of views on many critical items of policy," Gregg said in a statement released by his Senate office.

Gregg, 61, is a former New Hampshire governor who previously served in the House. He has been in the Senate since 1993 and currently serves as the top Republican on the Senate Budget Committee, where he is known as a crusader against big spending.

He was Obama's second choice to fill the Commerce portfolio.

New Mexico Governor Bill Richardson withdrew several weeks ago in the wake of a grand jury investigation into alleged wrongdoing involving state contracts. He has not been implicated personally.

In his statement, Gregg thanked Obama for the nomination, and said, "I especially admire his willingness to reach across the aisle."

In citing the stimulus and census, he said, "Prior to accepting this post, we had discussed these and other potential differences, but unfortunately we did not adequately focus on these concerns. We are functioning from a different set of views on many critical items of policy."

- AP