The Belgium international is keen to join Antonio Conte’s side this summer and is considered a top target by the Nerazzurri hierarchy.
However, the costs of a potential deal are a big obstacle for the Serie A side, with United understood to be demanding £75 million up front.
Lukaku’s representative Federico Pastorello held talks with Inter director Giuseppe Marotta on Wednesday and revealed afterwards that a deal remains some way from completion.
"It was just a chat," Pastorello told Sky Italia.
"I spoke with the director (Marotta) to understand the club's intentions with the player. They will take the decisions, we can't put a time frame on it.
"What is clear is that if Inter want the player, they will need to get a move on.
He added: "Inter are seriously trying to sign him, they are all out for him. Goals are not always there to be reached, but it's a declared target. At the moment, it remains a complicated dream."
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