Eddie Hearn, promoter for Anthony Joshua, is not responding to the pressure from WBC heavyweight champion Tyson Fury.
On Saturday night, Fury was ringside in Manchester and told local reporters that Joshua had until Monday to sign their bout agreement.
After weeks of discussions, Fury's team sent a contract to Joshua and his handlers on Friday.
If a deal is reached, the fight would land in December.
"I'm sick of setting deadlines. They either want this fight or they don't," Fury said.
Hearn indicates that there are still a lot of issues to work out between the two sides - and those issues will not be worked out by Monday.
He believes Fury is being difficult to disguise his desire to fight Manuel Charr.
Another big issue is the network situation. Fury has exclusive deals with ESPN (in the United States) and BT Sport (in the UK), while Joshua is globally exclusive to streaming service DAZN.
"The conversations have been decent and are moving in the right direction, but there is a long way to go," Hearn told Seconds Out.
"Fury wants to fight Manuel Charr, it's pretty obvious, and the public are not the brightest if they actually think otherwise. I think there is no way this contract gets signed on Monday because there is still a lot to be done. This fight takes time. We waited 10 days to get the contract...all of a sudden he wants it signed in 24 hours. No chance.
"Once again, Tyson Fury has made a statement - 'I'm retired, I'm this, I'm giving my purse to the homeless, I am walking away from this fight on Monday.' Guess what? The fight isn't getting signed on Monday. So if you want to walk away from that, while we are all trying to make it - including your promo team - off you go."
Joshua, a former two-time beltholder, is looking to bounce back after suffering back to back decision losses to unified champion Oleksandr Usyk.