WBC heavyweight champion

Fury said last month he was "over" boxing but has since changed his tune, saying he would take on Joshua provided his terms were met.

"The fight has got to be for free," Fury said in an Instagram post.

"Free to air on television and all tickets go for free. No money is to be made off of this British, historic fight if it happens," he said.

"There's the terms, I'm in the driving seat, take it or effing leave it."

The 33-year-old British fighter had hinted at retiring after sixth-round knockout of Dillian Whyte in front of 94,000 fans at Wembley to retain his title on Saturday.

Speaking to Piers Morgan's TalkTV, Fury said he was deciding to leave boxing behind to spend more time with his family.

"I am done. Every good dog has its day," he said.

"Like the great Roman leader said, there will always be someone else to fight. When is enough, enough?

"I am happy, I am healthy. I still have my brains, I can talk, I have a beautiful wife, I have six kids, umpteen belts.

Undefeated Wilder beat Stiverne in January 2015 to win the WBC belt - the only one of his 38 fights to go the distance - and has successfully defended his title five times since.

However, a proposed defence against Luis Ortiz at the Barclays Center in Brooklyn fell through when the former WBA champion failed a drug test.

It was followed by Anthony Joshua's Principality Stadium showdown against Kubrat Pulev being changed late on when the Bulgarian suffered a shoulder injury. IBO, WBA, IBF champion Joshua takes on Carlos Takam in Cardiff on Saturday.