Tony Bellew still retains hope of winning a world heavyweight title but says he will not fight fellow Briton Anthony Joshua.
WBC cruiserweight champion Bellew, 34, produced an upset to stop David Haye in a heavyweight contest last month.
But when asked if he would fight WBA and IBF champion Joshua, Bellew said: "Absolutely not. I don't need that kind of fight. He's far too good for me."
His promoter Eddie Hearn said he could fight WBO champion Joseph Parker next.
New Zealand's Parker, 25, will defend his title against Romanian Razvan Cojanu in Auckland next weekend.
Speaking after Joshua's 11th-round stoppage of Wladimir Klitschko, Bellew said: "I'm still dreaming about winning the heavyweight world title but a different portion to the one AJ has."
The Liverpudlian said he was considering retirement following his surprise victory over Haye last month on his heavyweight debut.
But on fighting Parker, he added: "I say Eddie knows what he's doing."
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Promoter Hearn confirmed that an all-British Bellew-Joshua fight was not on the cards.
"Tony and Joshua are good friends," he told BBC Radio 5 live's Sportsweek programme on Sunday morning.
"Tony Bellew has got his eye on some of the smaller guys. Fighters like Joshua are giants and Bellew isn't, but he's in the mix we talk about for challenging for world heavyweight titles."
Bellew is not a natural heavyweight, having stepped up from the cruiserweight division to fight David Haye in March.
He weighed in at 96.6kg for that fight, while Joshua was at a career heaviest of 113 kg against Klitschko on Saturday - a difference of almost 20kg.
But also in the mix for Bellew is WBC heavyweight champion Deontay Wilder - and the American wants a unification fight against Joshua, should he take the WBO belt off Parker.
"My plans are to get the WBO belt and once I get that, if I'm given a mandatory challenger, get that out of the way and set up a mega fight early in 2018," said Wilder.