De Gea, 31, has been United’s No.1 for the majority of his time since joining United in 2011 and, in a torrid campaign for the club, is one of the few players to have performed well this season.
The Spaniard’s contract runs out next summer and the Red Devils are reportedly planning an extension to his deal with incoming manager Erik ten Hag keen to keep the goalkeeper.
However, Phillips, the former Sunderland striker, thinks United’s squad needs freshening up after a disappointing campaign where they are set to finish outside the top-four and has called on the board to let De Gea leave.
Speaking to Football Insider, he said: ‘In my opinion, I think they should be moving him on. I think with the new manager coming in, that would be the best course of action.
‘You get to a stage in your career where you’ve been at a club a long time, like Rashford and De Gea, and things need to change. They need fresh faces through the door – and maybe they could even go down a younger route.
‘I think De Gea is on borrowed time at United along with many other players. It’ll be interesting to see if that contract materialises when Ten Hag comes in.’
After briefly losing his starting place to Dean Henderson last season, De Gea has regained some of the form which saw him named in the PFA Team of the Year four times in a row between 2014 and 2018.
In 2015, he was close to leaving Old Trafford to join Real Madrid but was denied a move back to Spain when paperwork was submitted after the deadline.
De Gea has been committed to the Red Devils ever since but could eye a move away from Manchester with the club nearly five years without a trophy and set to embark on another overhaul of the squad.
However, speaking earlier this year, he suggested he would be happy to stay at United for the rest of his career.
He told UEFA.com: ‘I like the fact I was born in Madrid, but at the end of the day, it’s just a city. Now I feel as if I’m from Manchester – I just feel like anyone else from Manchester.
‘Where you are loved and welcomed is your home. I’ve been here for many years and, obviously, anything can happen in life, in the world of football, but honestly, I don’t see myself away from Manchester United.’
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