Aston Villa boss Paul Lambert has warned they could be forced to pass on signing permanently Tom Cleverley.

Lambert will look to trigger the £7.5million purchase of Cleverley from Manchester United once the January window opens but admits Aston Villa owner Randy Lerner and the player himself must agree first.

"We've got the option to buy in January. I will definitely try. A lot will depend on finances," said Lambert.

"We've had one or two discussions with (chief executive) Tom Fox and Randy. If something comes up and he thinks it's right for the club and affordable, I'm pretty sure he will look at it.

"I will have a discussion with Tom. I've never really had that with him. He's still a Manchester United player. I've got him for a season anyway."