Washington  - Doctors have given John McCain, a former Vietnam prisoner of war who would be the oldest president ever to start a first term, a clean bill of health as part of a comprehensive release of his medical records Friday.

McCain, the 71-year-old presumptive Republican nominee, was repeatedly tortured in a Vietnam prison camp for more than five years and his movement has been hampered ever since.

The Arizona senator has also suffered repeated cases of skin cancer that have been surgically removed four times since 1993, according to a statement from the Mayo Clinic in Arizona, which has been involved in McCain's treatment since 1992.

"I can find no medical reason or problems that would preclude Senator McCain from fulfilling all the duties and obligations of president," said John D Eckstein, an internal medicine specialist who has taken care of McCain for 16 years.

Presidential candidates are not required to release their medical records, but McCain had come under pressure to provide the information due to his advanced age.

Ronald Reagan is the oldest-ever president, first elected in 1980 at age 69 and re-elected four years later. McCain will be 72 by the time of the November general election.

McCain carries a visible scar on the left side of his face from an invasive melanoma - a potentially serious form of skin cancer - that was removed in 2000.

The other three cases of melanoma were non-invasive, and none of the four cases have recurred since they were removed.

McCain has regular health evaluations and last visited with the clinic's doctors earlier this month. Eckstein said he "enjoys excellent health and displays extraordinary energy."

The Mayo Clinic's report also revealed McCain has small kidney stones in his right kidney and takes medication for allergies, cholesterol and occasional sleeping problems. (dpa)