Controversial sprinter Dwain Chambers intends to compete at this summer's World Championships in Berlin.

The reformed drug cheat, who was Europe's fastest 100m performer last summer but was not eligible to compete in the Olympics, is adamant he can win a medal over that distance for Britain this August.

Chambers last ran in a British relay team in controversial circumstances when they won gold at the European Championships in Gothenburg in 2006.

His recall to a squad suffering injury problems prompted Darren Campbell to refuse to do the customary lap of honour in protest at his inclusion.

From an athletics point of view, no-one doubts Chambers would be a valuable asset, adding experience to a squad which suffered the embarrassment of failing to get the baton round in Beijing last summer and not qualifying for the Olympic final.

A UK Athletics spokesman reiterated his eligibility to return, saying: "We would expect any athlete who pulls on a Great Britain & Northern Ireland vest to show a full commitment to our anti-doping programme, which is why, when Dwain Chambers returned to athletics for the third time last year and was not part of the UK Sport testing register, UK Athletics objected to his inclusion in the GB & NI squad.

"UKA operates within the legal frameworks of both the IAAF and WADA (World Anti-Doping Agency), therefore there is no question over the eligibility for selection of Dwain Chambers - who has now spent more than 12 months on the out-of-competition register - for the GB & NI team for the 2009 IAAF World Championships in Berlin."

Chambers has already been approached by Michael Khmel, UKA's head coach of sprints, to rejoin the relay squad now he has been welcomed back fully into the team's structure, but is unsure whether it would be a positive move.

The 30-year-old Londoner is known to be considering the offer but, as it has been suggested it might only be for this year, he feels there may be no point committing himself to what would be a short-term contract.

Chambers realises this is a strong possibility, for although he was given a clean bill of health by UKA, he is still banned for life from taking part at future Olympic Games, which means he would be omitted from the London 2012 relay squad.

New head coach Charles van Commenee arrives next month, and UKA are almost certain to embark on a development programme for the relay squads building towards the high-profile Games.

That would enable van Commenee and Khmel to to use next year's European Championships and the 2011 World Championships for team members to cement a closer relationship and improve their baton changing and other techniques.

Meanwhile, should Chambers qualify at the UK trials and then opt only for the 100m in Berlin, he would still be included as part of the British relay team, in accordance with IAAF regulations.

That offers the possibility of a re-enactment of what occurred in Gothenburg, for despite Campbell's protest, Chambers played a vital part in their success.