United must now agree a fee with Arsenal after the World Cup, but Vermaelen hopes to move to Old Trafford and is preparing to leave the Emirates.
Central defender Vermaelen only has one year remaining on his Arsenal contract and has found himself pushed out of manager Arsene Wenger’s first-choice team by Laurent Koscielny and Per Mertesacker.
New United manager Louis van Gaal is desperate to strengthen United’s defence and believes Vermaelen can find his best form under him.
The 28-year-old has been at Arsenal for five years after signing from Dutch club Ajax. He got off to a superb start with the Gunners, but injuries curtailed his progress.
Vermaelen earns around £70,000-a-week and it is understood he has verbally agreed a deal with United that would see him pocket around £100,000-a-week.
Arsenal cannot expect to receive more than £10million for Vermaelen with only a year remaining on his contract.
Vermaelen is currently with the Belgium squad in Brazil for the World Cup, but wants his future sorted out as quickly as possible once the tournament ends.
He shares the same agent as Robin van Persie and that is understood to have been key to United’s interest.
Arsenal have been preparing for the possible departure of Vermaelen by lining up a number of defensive targets including Steven Caulker and Virgil van Dijk.
Although Vermaelen is not a first-team starter for Arsenal any more, his departure to United would be another blow for Wenger after losing Bacary Sagna to Manchester City.