Libyan leader Moammar Gadhafi must leave power and Libya to stop the NATO military strikes in the country, U.S. Secretary of State Hillary Clinton has said.

"I don't think there is any mystery about what is expected from Mr. Gadhafi at this time," Clinton told reporters on Wednesday.

Earlier, Gadhafi urged U.S. President Barack Obama to end the NATO bombing of his war-torn country. Gadhafi made the appeal in a letter, a senior administration official said.