WASHINGTON, Feb 24 (Reuters) - U.S. President Barack Obama on Tuesday signaled a break with controversial interrogation techniques used under his predecessor George W. Bush, saying the United States "does not torture."

Obama also vowed "swift and certain justice for captured terrorists." The Democratic president, in office just five weeks, has previously ordered the closure of the U.S. detention center at Guantanamo Bay, Cuba, where many terrorism suspects have been held for years without trial.

"Living our values doesn't make us weaker, it makes us safer and it makes us stronger. And that is why I can stand here tonight and say without exception or equivocation that the United States of America does not torture," Obama said.

The United States has faced sharp criticism from human rights groups for employing methods such as water-boarding, which simulates drowning, in the interrogation of suspects.

(Editing by Frances Kerry)