Britain’s Mirror newspaper said Sanchez was due to arrive in Manchester with agent Fernando Felicevich, with a medical scheduled for Sunday afternoon, while Sky reported that Mkhitaryan would have a medical in London.

The Mirror said the deals may not be officially completed until Monday as both Sanchez and Mkhitaryan are non-EU players and must have their work permits ratified by their new clubs.

Sky Sport News showed Armenian international Mkhitaryan at a central London hotel on Saturday evening alongside agent Mino Raiola ahead of his expected move.

Arsenal boss Arsene Wenger and United manager Jose Mourinho both said they expected the two-way deal between the Premier League rivals to go through.

Wenger said Chile international Sanchez was absent from the Arsenal squad on Saturday because he was close to completing a deal that has been in the making since United out-bid Manchester City for the former Barcelona star.

“I expect soon or never,” Mourinho said after his side’s 1-0 win against Burnley. “I think it is so close, so close, so close that if it doesn’t happen it’s not going to happen.”

“So I am positive, I know my people are doing everything they can — the owners with the green light, Mr (executive vice chairman Ed) Woodward working hard… and everybody is giving everything they can and I think they are going to be successful,” he added.

Sky said it understood it could be a straight swap deal but details were yet to be finalised.