South Carolina Governor Mark Sanford today admitted to having an extended affair with an Argentinean woman, and announced his resignation from the Chairmanship of the Republican Governor’s Association at press conference, effectively ending his political prospects for higher office.

Sanford confessed to having an affair for the past year and said his wife and family have known about it for the past five months.

His mysterious disappearance from the state last week drew widespread interest after his aides first said they didn’t know where he was and then later said he was hiking on the Appalachian Trail but unreachable while his wife said he was away writing.

Upon his arrival at Atlanta airport on Wednesday morning, Sanford was spotted by a reporter from The State.

At the press conference, Sanford apologized to his wife, his children, his staff, the people of South Carolina and of the US.

The bottom line is this: I have been unfaithful to my wife. He added: I have spent the last five days of my life crying in Argentina.

Sanford told the press conference he was resigning as chairman of the Republican governors' association but said nothing about resigning as governor.

Sanford is the second politician within about a week to confess to having an extramarital affair. Last week, Senator John Ensign, Republican of Nevada, disclosed that he had had a relationship with someone who worked on his campaign staff.