Parent club Shanghai Shenhua had been demanding Ighalo return to China ahead of the new Chinese Super League season, due to kick-off next month.
Ighalo’s current loan expires on Monday, but United were working to retain his services until the end of the season.
Negotiations looked to have reached a standstill, but it seems a deal could now be back on.
“On the one hand, the Super Eagle [Nigerian] feels very good in Manchester with which it is very close to a salary agreement,” Ighalo’s agent Ladi Salami told FootMercato .
“Negotiations with the Chinese are ongoing and are going well.
“On the other hand, in view of the latest regulations in force in the Middle Empire, it is almost impossible to offer such amounts.”
Since his arrival in January, the forward has scored four times in just three starts, and has made a valuable contribution as part of United’s squad.
Shenhua did offer Ighalo a two-year contract extension earlier this year worth £400,000 per week, but he has his heart set on remaining at Old Trafford.
Reports have suggested United could make Ighalo’s move permanent, but for now at least they are just trying to keep him until the campaign has reached its conclusion.
United boss Ole Gunnar Solskjaer had confirmed earlier on Tuesday that the club were doing everything possible to keep Ighalo on their books.
Solskjaer said: “The loan deal went until the end of May now, so obviously he’s supposed to be going back.
“We’re in dialogue. They’ve been great towards us, his club, and allowed him to play for his dream club.
“It’s been a dream for him and hopefully he can finish off what he started, hopefully with a trophy for us.
“At the moment, nothing has been agreed. Their league is going to get started soon so we’re just waiting to see.”
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