South Carolina governor Mark Sanford confessed to having been in an extramarital affair with an anonymous Argentinean woman today during a press conference with reporters and offered his resignation as chairman of the Republican Governors Association.

Gov. Sanford - who was considered by some as a potential presidential candidate for 2012 - had been missing for six days but returned to the U.S. on Wednesday from a secret private trip to Argentina. His staff told reporters that the governor was hiking on the Appalachian trail.

I've been unfaithful to my wife, ABC reported today.

We developed a remarkable friendship over those eight years and then as I said about a year ago it sparked into something more than that, Sanford told reporters, according to the network.

Gov. Sanford said his wife was aware of the affair and his family had been trying to work through the situation for about the last five months, ABC notes.

The Governor did not say if he was resigning as the head of the state.

Watch a video of the press conference below: