Jota is desperate to leave Al Ittihad just months after joining the Saudi Pro League club in a £25million deal.
The 24-year-old was not registered for the club's domestic squad despite becoming their record signing in the summer.
As a result, his game time has been severely limited, and it is understood Al Ittihad are happy to cut their losses.
The Hammers are in desperate need of attacking cover after Michail Antonio suffered a setback in his recovery from a long-term hamstring problem.
talkSPORT understands they face competition to sign Jota from two unnamed top-flight clubs in England.
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The Portuguese forward made a name for himself at Celtic Park, scoring 21 goals and bagging 21 assists over two seasons as Ange Postecoglou's Hoops dominated in Scotland.
With a number of big European clubs monitoring Jota, his move to Al Ittihad came as a shock.
He joined superstars Karim Benzema and N'Golo Kante at the Saudi club, run by the nation's Public Investment Fund, but Al Ittihad's season has not gone to plan.
They are currently seventh in the Saudi Pro League and recently parted company with manager Nuno Espirito Santo, who quickly took charge at Nottingham Forest.
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Jota has been restricted to appearing in cup competitions since September, with Saudi clubs restricted to naming eight foreign players in their domestic squads.
As a result, he has only managed two goals since making the move to the Middle East.
It is understood the Benfica academy graduate would need to take a significant pay cut from his £200,000-a-week wages to join West Ham.
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