He was Leader of the Ulster Unionist Party ( UUP ; 1995 â `` 2005 ) , the first First Minister of Northern Ireland ( 1998 â `` 2002 ) , and was a Member of the House of Commons ( 1990 â `` 2005 ) . He served as Leader of the Ulster Unionist Party ( UUP ; 1995 â `` 2005 ) , was the first First Minister of Northern Ireland ( 1998 â `` 2002 ) , and was a Member of the British Parliament ( 1990 â `` 2005 ) .