Washington Mutual debt protection costs jump

NEW YORK, March 6 (Reuters) - The cost to insure the debt of Washington Mutual Inc WM.N jumped to a new high on Thursday after Standard & Poor's cut its ratings on the largest U.S. savings and loan due to expectations of worsening mortgage loans.

WaMu's credit default swap spreads widened to 636 basis points, or $636,000 per year for five years to insure $10 million in debt, from 540 basis points at Wednesday's close, according to Markit Intraday. The swap had closed at 617 basis points on Jan. 9, its previous widest level. (Reporting by Karen Brettell; Editing by Jonathan Oatis)