FA officials have been told that work at Wembley is on schedule, which would mean a return to London for the cup final for the first time since 2000.
Since 2001, the showpiece game has been played at the Millennium Stadium and Mr Sergeant said the venue was ready to host the match if needed.
He added: "We'd love to have the FA Cup final back here in Cardiff one more time. My sympathy goes out to Wembley - they've got a lot of work to do.
"Our position at the moment is that we know the date of the final, we'd love it to come to the Millennium Stadium and the FA know we're here and waiting."