Arsenal were interested in Henrikh Mkhitaryan when he left Borussia Dortmund for Old Trafford in 2016
Manchester United will only sign Arsenal forward Alexis Sanchez if Henrikh Mkhitaryan moves the other way, says Gunners manager Arsene Wenger.
United boss Jose Mourinho said his club were "doing absolutely everything they can" to sign Sanchez, who missed Arsenal's 4-1 win over Crystal Palace.
Wenger said: "He didn't play because you cannot drive up north and play football at the same time."
Armenia midfielder Mkhitaryan sat out United's 1-0 victory over Burnley.
Wenger said: "Sanchez will only happen if Mkhitaryan comes. That's why it takes longer."
United have appeared to be on the brink of signing Sanchez since Premier League leaders Manchester City ended their pursuit of the Chile forward on Monday.
Wenger said after last week's defeat at Bournemouth that Sanchez's future would be resolved "within 48 hours". Six days on, he gave the same timescale.
The Frenchman said: "January has been difficult for us, destabilising. We have had big players concerned with moving away which causes uncertainty.
"The deal happens only one way, if the other way happens as well, that's why it takes longer as well because it has to be co-ordinated.
"I expect it to happen. In the next 48 hours it will be decided."
Mourinho also remains confident Sanchez - whose contract expires at the end of the season - will end the transfer window at Old Trafford.
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Gossip column extra: Sanchez to Manchester United and Mkhitaryan to Arsenal
"If you ask me if I think he is coming, I think so, but I have no confirmation," Mourinho said.
"Expect soon or never. So close, so close, so close, if it doesn't happen it is not going to happen.
"I know my people are doing absolutely everything they can. I think they will be successful."
Wenger also said "nothing is happening" with his side's interest in Borussia Dortmund striker Pierre-Emerick Aubameyang.
The 28-year-old Gabon striker was left out as his side drew 1-1 at Hertha Berlin on Friday, but Wenger said: "Aubameyang, no.
"He can be left out of the Dortmund team for different reasons, certainly not for transfer reasons at the moment."
Find all the latest football transfers on our dedicated page.
Source: bbc.com