Greek Prime Minister Andreas Papandreou underwent open-heart surgery Friday, and a Greek Embassy spokesman said "Everything is fine."

Dr. Nicholas Papadakis, the Greek Embassy press attache, added: "The operation was successful."Greek officials at the hospital said a team headed by Magdi Yacoub, Britain's top heart surgeon, performed the six-hour operation on the 69-year-old Socialist prime minister at Harefield Hospital north of London.

The prime minister's four children and his girlfriend, airline stewardess Dimitra Liani, 34, were at the hospital throughout the surgery.

Shortly after the operation, hospital general manager David Thomson told reporters that Papandreou "underwent an operation for replacement of his aortic valve using a human valve. This was combined with insertion of three bypass grafts and the clearing of the diseased coronary artery, to improve the heart function."