Sources claim discussions to that affect have been held between the clubs.
The Brazilian top flight does not start until March, which could – in theory – clear the way for such a deal.
But any agreement for Paqueta to stay in London until the final game of the season in May could depend on how far adrift West Ham are from safety.
They are currently seven points adrift of Nottingham Forest, who occupy 17th place.
Paqueta missed last weekend’s FA Cup third-round win over Queens Park Rangers, which sparked claims from insiders that he did not make himself available because he wants to leave.
However, club sources insist Paqueta’s absence was down to a minor injury.
It now remains to be seen whether Paqueta is selected to play against Tottenham in the Premier League on Saturday.
West Ham boss Nuno Espirito Santo says the club need to find an answer quickly.
Speaking on Thursday, he told reporters: “We always want our best players to be involved and Lucas is one of our best players, so let’s try to solve the situation.
“It’s a solution that we have to find. Us as a club, the player, myself.”