Wall Street recovered nearly 190 points after Standard & Poor's affirmed its ratings for Ambac Financial Group Inc. and MBIA Inc., raising hopes that troubled bond insurers will emerge from the credit market crisis on solid footing.

There has been speculation that Ambac might find sufficient capital early this week to hold onto the stellar "AAA" rating it needs to remain in the municipal bond business. Rating agencies including S&P have been under pressure to downgrade the insurers after they had weakened their financial positions by insuring subprime mortgage securities that later collapsed.

Charlie Smith, chief investment officer at Fort Pitt Capital Group, said the pronouncement by Standard & Poor's was easing Wall Street's fears that the major investment banks would have to book further write-downs on their debt, having suffered billions of dollars in losses during the fourth quarter. Had bond insurers lost their highest ratings, the bonds they back would likely see their ratings lowered and forced the sale of some investments.

"This is essentially evidence that S&P has signed off any tentative deal," said Charlie Smith, chief investment officer at Fort Pitt Capital Group.