David de Gea
De Gea is yet to sign a new contract at United, which has less than 18 months to run.Getty Images

Real Madrid are unlikely to make a bid for Manchester United goalkeeper David de Gea given their wealth of options, according to former president Ramon Calderon.

Last week's signing of Victor Valdes has sparked rumours that De Gea could leave Old Trafford as the club continues to stall on securing the Spanish international to a new contract.

Calderon, who was president at Bernabeu from 2006-2009 and influential in signing three-time world footballer of the year Cristiano Ronaldo from United, says he expects Iker Casillas to remain as No.1.

"We already have the best goalkeeper in the world, which is Casillas," the 63-year-old told Talksport. "We also have brought Keylor Navas. I don't see any need to get any other goalkeeper.

"De Gea is perhaps also one of the top five goalkeepers in the world but I think Casillas can still be at the top for three or four more years. Navas is a young goalkeeper so I don't see any need [for De Gea]."

United manager Louis van Gaal has refused to discuss in detail the prospect of De Gea being handed a new contract in the near future, with the 24-year-old having less than 18 months to run on his current deal.

"De Gea has developed himself in the six months that I've been here very much," Van Gaal said. "I'm very pleased with his development. I think there is no problem for him to sign.

"When you are a (regular) player, then probably you are the best, and then the manager is very happy that a player that is fixed in the line-up will stay."

After a difficult first season at United, De Gea was voted into the Premier League team of the season last term and has recaptured that form during the current campaign, having produced a series of stunning performances to spearhead the club's Champions League charge.

De Gea's future at the club will however continue to be shrouded in doubt until a new contract is agreed, with reports already abound that Real are ready to capitalise on the uncertainty.