LONDON - World heavyweight champion Lennox Lewis will not fight Mike Tyson on April 6 but he has not ruled out facing the embattled fighter later in the year.

"The April 6 date is definitely out of the window for the Tyson fight, but it may be okay for another fight," Lewis told BBC Radio.

"I think on that day I will defend my titles in Las Vegas against the official IBF challenger Chris Byrd."

However, Lewis, the IBF and WBC champion, said he hopes to reschedule a fight with "Iron Mike" Tyson at a later date.

"Later in the year for a Lewis-Tyson fight -- definitely," 36-year-old Lewis added.

"Mike Tyson is the ultimate match-up in my era and it would be disappointing not only for me but for the public not to see that match-up."

The bout, originally scheduled to take place in las Vegas, was thrown into doubt by the refusal of the Nevada state athletic commission to grant Tyson a boxing licence.

The decision followed a mass brawl last week at a new york press conference where Lewis claimed that Tyson had bitten him on the thigh.