WBC heavyweight king Vitali Klitschko says that Britain's WBA champion David Haye is scared to fight him or his brother, IBF and WBO holder Wladimir.
"Haye has twice jumped away because he is afraid," said 39-year-old Vitali.
The Ukrainian made the statement as he offered hope that a Haye fight could be made this year as his planned bout with Shannon Briggs, 38, is not yet sealed.
Briggs, in Cardiff with Vitali for a WBC boxing festival, said on Thursday that they would meet on 16 October.
If that fight goes ahead it is expected to be in Hamburg, while Wladimir, 34, will take on Nigeria's Samuel Peter in Frankfurt on 11 September.
Briggs on Klitschko and Haye
"Haye doesn't want to fight," said Vitali. "He talks so much, but he has to be honest with people.
"[The Klitschkos] are ready to fight him anytime. We'll split the worldwide income 50-50 - I think that's fair.
"Right now David Haye is missing. If he's afraid to fight, he needs to tell everyone and stop the talk.
"If he's ready, let's sign the contract and talk in the ring with our fists, not with our mouths."
Former WBO champion Briggs said on Thursday that he had received the contract for the Vitali fight on Wednesday and was heading back to his hotel to sign it.
"I look forward to retiring a great champion - I'm the best ever!" said Briggs, who is known as 'The Cannon', has a record of 54-5-1, and whose 27 first-round knock-outs is the most by any heavyweight champion.
"Hopefully when I retire Vitali can fight David Haye at Wembley Stadium, that would be a dream come true."
But Vitali, responding to the prospect of fighting Briggs, stated: "We're in the negotiation process.
"If we finish the contract, hopefully in a couple of weeks it can be done. If not, it will be another opponent."
Klitschko's most recent win was over Poland's Albert Sosnowski in May 2010, while New Yorker Briggs' most-recent bout was a victory over Rob Calloway in May.
In March 1998, Briggs - eighth in the WBC rankings - took on then-WBC world champion Lennox Lewis in Atlantic City but was stopped in five rounds.
In April, Briggs claimed: "The Klitschkos hurt the division with their safety-first styles. Neither one of them puts it on the line."
He urged Haye to bypass the Ukrainian siblings in favour of fighting him instead, adding: "We don't have to deal with the Klitschkos, hand-picking opponents and fighting only in Germany with their boring styles."
Vitali Klitschko says he is enjoying his weekend in the Welsh capital
Saturday saw a high-quality amateur boxing night, where Team GB drew 6-6 with an impressive rest-of-the-world squad made up of fighters from Sweden, the United States, Ireland and China.
The event culminates with the Night of Champions at the Cardiff International Arena on Sunday with over 80 former and current champions expected to attend, including Vitali Klitschko, Roberto Duran, Carlos Zarate, Sergio Martinez and Earnie Shavers.
"I got in to Cardiff on Wednesday and I'm loving it - I may not leave," Briggs told BBC Sport Wales.
"It's an honour to see these living legends."
Vitali, known as 'Dr Iron Fist', added: "I'm happy to be in Cardiff, the Night of Champions has so many big boxers and historical persons.
"You think of Muhammad Ali, Lennox Lewis, Mike Tyson, Sugar Ray Leonard... they've all held the WBC belt. It's the past and the future of boxing."
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