WASHINGTON - New Mexico Gov. Bill Richardson says he is withdrawing his nomination to be president-elect Barack Obama's commerce secretary amid a grand jury investigation.

Obama said in a statement Sunday that he accepted Richardson's withdrawal "with deep regret" but that the governor was putting the country first to avoid any delay in filling the cabinet post.

A federal grand jury is investigating how a California company that contributed to Richardson's political activities won a New Mexico state contract worth more than $1 billion.

Richardson says in a statement issued by Obama's transition team that the investigation could take weeks or months and he couldn't ask Obama to delay the Commerce Department's work.

Richardson says the investigation will show that he "acted properly in all matters."