A Premier League inquiry into alleged transfer irregularities has found that 17 transfers, including the moves of Didier Drogba and Petr Cech to Chelsea, cannot be cleared, the league said on Friday.
The transfers involve five clubs - Chelsea, Portsmouth, Middlesbrough, Bolton Wanderers and Newcastle United, while the inquiry questions the roles of more than a dozen agents and advisors, notably top Israeli agent Pinhas Zahavi.
A league statement said the inquiry found Zahavi "has failed to co-operate fully" and recommended that FIFA, world soccer's governing body "launch their own inquiry into the conduct of Mr Zahavi based on the evidence obtained."
The probe, started in March 2006 by former London police chief John Stevens, looked into 362 moves completed between January 1, 2004 and the end of January last year.
Though clubs had fully co-operated and there was no evidence of irregular payments, known as "bungs", the outstanding issues with Zahavi and fellow agent Barry Silkman meant five deals they were involved with could not be cleared.
They covered Chelsea's signings of Ivorian striker Drogba and Czech goalkeeper Cech, Zambia striker Collins Mbesuma's move to Portsmouth and the Middlesbrough moves of Brazilian midfielder Fabio Rochemback and Nigeria striker Yakubu Aiyegbeni.
Another Chelsea transfer, which brought Ghana midfielder Michael Essien to the club, has not been cleared because of unanswered questions over another agent and an advisor involved in that deal. The report also said it had concerns about the involvement of Craig Allardyce, the son of then Bolton Wanderers manager Sam, when he acted as an agent in the club's signing of Ali Al-Habsi, Tal Ben Haim and Blessing Kaku.
It also highlighted the "conflict of interest" involving son Craig, his father Sam and the north-west club. Newcastle were brought into the inquiry due to a lack of cooperation by agents involved in the signings of Turkish midfielder Emre Belozoglu, French defender Jean Alain Boumsong and French midfielder Amady Faye. The inquiry also found Newcastle's former manager Graeme Souness had provided information which contained inconsistencies.
One of the 17 transfers was not identified, so as not to prejudice an inquiry "by another regulatory authority." The report also recommended inquiries should be continued into the registering of a race horse by an agent, Willie McKay, in the name of Portsmouth manager Harry Redknapp.
"Harry Redknapp has confirmed that this could well have happened though it was a very unsuccessful horse that resulted in no material gain or reward for him," the report said.
The Premier League said on Friday: "All outstanding matters, together with full and relevant documentation will now be passed to the FA and FIFA who have the required powers to investigate further and consider the next appropriate steps."