Rio Ferdinand says Man Utd should "move heaven and earth" to sign Mbappe or Haaland.

The former Man Utd defender has been happy to see the "progress" made by his old club but says there's "room for improvement".

Dortmund sensation Erling Haaland has become the hotcake for big clubs in Europe. [Getty]

Ferdinand insists that Man Utd should pounce on the opportunity to sign Haaland or Mbappe if they can.

Former Manchester United defender Rio Ferdinand has urged his former side to "move heaven and earth" to secure the services of either Dortmund striker Erling Haaland or PSG forward Kylian Mbappe.

Ferdinand, who had trophy-laden years at Old Trafford, believes United need a quality hitman in their attack to take them to the next level.

Both players - Mbappe and Haaland - are quickly developing into the leading stars of the beautiful game and could be on the move this summer.

"Manchester United were playing catch up from everybody last season," Ferdinand told the FIVE YouTube channel. "They finished 30 points behind Liverpool last season, now they’re above them.

"That’s a big, big achievement in that sense. We were not sitting there last season thinking Manchester United would win the league this season or be up there.

"Four or five weeks ago we were saying that, so I see that as a massive step in the right direction. Is this team in a better position than they were last season? Yes, they are. Is there still work to do? Yes, there is. But I see progress."

The ex-QPR centre-half continued: "I still see room for improvement, we definitely need to buy a centre-back, a commanding centre-back with pace, please!

"I think [Edinson] Cavani, yes, he’s a good stopgap but [we need] a centre-forward. If people like Erling Haaland or Kylian Mbappe are available, you can’t allow them to go somewhere else and you need to move heaven and earth to get them here.

"Manchester United are used to having superstars and those boys would change the narrative at this football club, that’s how good they are.

"There’s room for improvement and opportunity to improve this squad, there are players out there available, it seems. We need to be in the mix."

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