WASHINGTON (Reuters) - Defense Secretary Chuck Hagel warned on Wednesday the Pentagon would have to take draconian steps next fiscal year, including hiring freezes and cuts in weapons purchases, unless Congress acts to stop $52 billion in spending cuts.

"I strongly oppose cuts of that magnitude because, if they remain in place for FY 2014 and beyond, the size, readiness and technological superiority of our military will be reduced," Hagel wrote in a letter to the top Democrat and Republican on the Senate Armed Services Committee released on Wednesday.

(Reporting by Phil Stewart; Editing by David Brunnstrom)