Chelsea starlet signs loan deal.Clifford has been with the Londoners since he was a young boy and has already been involved in Champions League squads.
"I'm really glad that we have secured his services and I'm sure that he will add to the quality we already have in the squad."
"He has been in Chelsea's first team squad on occasions already and I have been very impressed with what I've seen of him.
He told the official website: "He is an exciting youngster with plenty of ability that we will benefit from in the coming weeks.
He played forty five minutes for Chelsea's U21s on Thursday night, a game that Joe Dunne attended and the U's boss is pleased to have got Billy on board.
The Chelsea youngster put pen to paper on Friday morning, before training with his new U's teammates.
Billy Clifford has joined the U's on a month's loan.
He will take on the number forty one shirt for the U's and will be in the squad for the game against Scunthorpe providing the relevant authorities rubber-stamp the move.
If you would like to sponsor Billy's kit, call the Commercial Team on 01206 752020.