West Ham have offered to meet Celta Vigo the £44.85m (€50m) release clause for striker Maxi Gomez, according to Sky sources.
Sky Sports News understands discussions are ongoing with regards to the method of payment.
Under La Liga rules, West Ham can trigger the striker's release clause by lodging the full amount directly at La Liga's headquarters in Madrid.
The Premier League side, however, are proposing to pay the £44.85m amount in instalments and therefore will need to negotiate a structure which will be accepted by Celta Vigo.
Valencia have rivalled West Ham's interest in Gomez, but it is understood the Hammers are prepared to pay double what the Spanish side are offering and will use the proceeds from the sale of Marko Arnautovic to Shanghai SIPG to fund the deal.
Valencia had initially reached an agreement which involved three players (including former Celta Vigo forward Santi Mina), plus cash, in exchange for the player.
But Sky sources believe this deal went as far as the three players arriving in Vigo for medicals - only for those to be halted when Gomez expressed his wish to move to the Hammers instead.
Although both West Ham and Valencia previously had offers of £29m, plus add-ons, accepted by Celta, they are now believed to be demanding the £45m release clause in the Uruguayan's contract.
It is understood an agreement over personal terms has been agreed in principle with West Ham hoping they can finalise the move next week.
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