Gary Neville and Roy Keane agree on what Manchester United should do with David de Gea

Gary Neville has vowed that Manchester United need to sign a world-class goalkeeper as he reflected on David de Gea's time at Old Trafford, while Roy Keane also believes the Reds should move on from the Spaniard because he has made 'far too many mistakes'.

De Gea's contract at United expired on June 30, so he is technically now a free agent, although talks over a new contract are expected to resume after his wedding this weekend.

The 32-year-old has made nearly 550 appearances for United after joining from Atletico Madrid in the summer of 2011. In that time, he has won the Premier League, Europa League, FA Cup, and two League Cups.

De Gea had agreed to stay at United on a significantly reduced salary, only for United to pull the plug on the deal and offer him an even lower wage. An agreement is yet to be reached, which is why his deal was allowed to expire on Friday.

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United are in the market for a new goalkeeper this summer and former defender Neville believes a world-class addition in that department is needed.

"I don't want to have a go at a goalkeeper who has been brilliant for Manchester United for the last ten years. He has had difficult moments and I didn't think he was good enough to be a Manchester United goalkeeper at the beginning," he told The Overlap Live.

"He was too slight, lacked the physicality. I gave him a lot of criticism. There was a period in the middle for four or five years where he was very good and performing at a high level. He was their best player when they were a poor team, but he still performed at a high level.

"Then in the last couple of years, he [Roy Keane] said it, you cannot let that goal in, the