LONDON, Aug 15 (Reuters) - The United States has no choice but to take action against Iraqi President Saddam Hussein, White House national security adviser Condoleezza Rice said on Thursday.

"We certainly do not have the luxury of doing nothing," Rice, a pivotal player in President George W. Bush's administration, told BBC radio. "We believe the case for regime change is very powerful."

But she added that Bush had not decided "how he wants to do it" or how to "make the case for particular methods".

Saddam, she said, had twice come closer than the West had thought to acquiring nuclear weapons.

"This is an evil man who, left to his own devices, will wreak havoc again on his own population, his neighbours and, if he gets weapons of mass destruction and the means to deliver them, on all of us," she said. Nampa-Reuters 0807 150802 WEB story ENDS (NAMPA 150811)