Fury had his sights set on a showdown on a unification bout with WBA, WBO and IBF champion Oleksandr Usyk at the end of 2022, but has now had to turn his attention elsewhere after it emerged the Ukrainian would not be able to box again this year.

The 34-year-old has since offered Joshua, who lost his rematch with Usyk last month, the opportunity to face him before the end of 2022 and on Tuesday posted an update with a video on his Twitter account further outlining his terms.

• 'I'll be ready in December': AJ responds to Fury | Warren: Offer sent
• Fury: Usyk doesn't want fight this year

"I'm being bombarded with messages on how much I'm going to pay AJ," Fury said. "Everyone is saying '80-20, 70-30, 75-25' - the actual answer is I've offered him 60-40.

"[That's] 40 per cent of this amazing fight because I want this fight to happen. He doesn't have any excuses now not to take it, he can't say I've low-balled him or offered him 20 per cent or 30 per cent.

"I've offered the people 40 per cent - take it or leave it, let us know."

Joshua had initially responded to Fury's challenge by tweeting him to contact his management company along with vowing "I'll be ready in December".

Fury's promoter Frank Warren had confirmed they were making a formal offer to Joshua to contest the WBC belt too.

"It's us who have made the approach to give AJ a great opportunity to get himself back into the top level against the world champion Tyson," Warren told talkSPORT.

"He's willing to make that voluntary defence, so we'll send the offer across today [Tuesday] and then they'll have to look at it and decide whether they want to grab this with both hands.

"To his credit he has come out saying that he's up for it. I'm not bad-mouthing them or the other side, all we're interested in doing is making this fight."

Joshua's promoter Eddie Hearn expressed his doubts about whether the offer is serious, with the undefeated Fury having previously announced his intention to retire from boxing after successfully defending his title against Dillian Whyte in April.

However, Hearn is eager to get the all-British world title fight on if the offer is genuine and is adamant 2012 Olympic gold medallist Joshua is too.

"Personally, I don't believe Fury is serious about this, but if he is, which I said to the Warrens [Monday] night, 100 per cent we will sit down and make the fight," Hearn told talkSPORT.

"I would love to get really excited about this, because it's the fight that I get stopped in the street for more than any fight that could be made and it's a fight that AJ has wanted for a long time.

"Don't forget, we signed for this fight last year before the arbitration forced the Deontay Wilder fight for Tyson Fury.

"The message is quite clear from AJ, we don't want to get involved in a backwards and forwards, we want the fight, it's the fight he's wanted for a long time."