Saudi Arabian promoter Sela is fronting the bill for the prospective Joshua-Fury fight, with both men signing separate contracts with the company.
Joshua’s contract stipulates it must take place in the UK, leading to his promoter Eddie Hearn renegotiating details in that deal.
But after London Mayor Sir Sadiq Khan made a public plea for the fight to happen at Wembley, Hearn said talks about staging it in the UK had “re-opened”.
Sela and broadcaster Netflix are understood to favour New York’s Madison Square Garden.
Sport understands Sela has contacted the London mayor’s office in recent weeks about bringing the long-awaited contest to the national stadium, but have not progressed talks further since last week.
Hearn had said he hoped an announcement could happen in the coming week, but that now seems unlikely given the latest developments.
A bout at Wembley may need to happen in the early hours – which would draw in a larger television audience in the US.
Khan says his team would back such a proposal.
“A message to the promoters – we want to host it in London. Talk to us, we’re really keen to have it,” Khan told Sport on Thursday.
“I’m hoping the promoters understand that not only will you get 100,000 people watching this bout live, you’ll get millions watching it across the globe, where both boxers are cheered on by their loyal fans.”