Earl's WBU title is lightly regarded

Their fight will be the main support bout to the European Union heavyweight title clash between Michael Sprott and Audley Harrison at Wembley Arena.

Also on the bill will be Amir Khan, fighting at lightweight against an as yet unconfirmed opponent.

Luton's Earl took the WBU lightweight title last October with a gutsy points win over Argentine Angel Hugo Ramirez.

The 28-year-old has a 24-1 record, with 12 victories by KO, going into his meeting with Katsidis, 26, who is 21-0 with 19 knockout wins.

Earl is the WBO's number one-ranked contender, with Katsidis number two.

They will be fighting for the title vacated by Brazil's four-time world champion Acelino Freitas, who retired last October.

He secured the WBO crown in April 2006 with a split-decision win over Zahir Raheem of the USA.

However, the 30-year-old has since reversed his decision to quit the ring.

Khan moved up to light welterweight for his most recent fight in December, when he beat Rachid Drilzane for the IBF inter-continental belt.

The Bolton star, 20, claimed a points victory over the Frenchman but only after suffering a seventh-round knockdown.

He has since handed back the title, and sees his future in the 10-stone ranks, where he won Olympic silver in Athens in 2004.