Ben Okuly thought he was ready to propose to his girlfriend, but first he needed Paul McCartney's (search) approval.

Okuly was attending one of the former Beatle (search)'s concerts in suburban Detroit (search) when he held up a sign that caught the McCartney's eye: "CAN BEN ASK MELISSA TO MARRY HIM?"

During the concert last week, McCartney spotted it and read it out loud, The Detroit News reported Friday.

"Well, go on, get down on your knees and ask her, Ben!" Sir Paul ordered. Okuly did, and she said yes.

"Well, that's a first for me," McCartney quipped of the in-concert engagement. "And I hope it's a last for you, Ben."

The 26-year-old library employee hatched the plan when he and his girlfriend, Melissa Steele, were driving from Ohio to the concert.

"To have Paul McCartney be there and start the proposal, I really don't have words to describe what that was like," Steele told the newspaper.