The former US senator said it was a ‘special treat’ to return to the region for the tournament at Royal Portrush.

The peace envoy said his appearance at the Good Friday Agreement conference was in the balance until days before he flew out.

Bill Clinton, Hillary Clinton, Tony Blair and Bertie Ahern were among those who attended the ceremony at Queen’s University.

The former prime minister joined Bill Clinton and Bertie Ahern for a discussion to mark 25 years since the Good Friday Agreement.

The former US senator was delivering a keynote speech at the beginning of a conference to mark 25 years since the Good Friday Agreement.

Political leaders, past and present, are addressing a major conference in Belfast, 25 years after the signing of the Good Friday Agreement.

The event in Belfast will also be attended by Bill and Hillary Clinton and former taoiseach Bertie Ahern.

Mr Adams also said that while he does not believe a united Ireland is inevitable, he regards the historic peace deal as a stepping stone towards it.

Senator George Mitchell, one of the architects of the Good Friday Agreement, appeared before an Irish parliamentary committee on Thursday.