Probe into charges of match-fixing levelled against England's stand-in captain Alec Stewart, West Indies star batsman Brian Lara and other leading cricketers, are likely to be dropped unless bookie Mukesh Gupta agrees to provide formal evidence by July 1.

ICC's anti-corruption chief Sir Paul Condon told newsmen in London on Monday that he had issued an ultimatum to Gupta that unless he "lets us know by July 1 that he is willing to co-operate and give evidence either in India or outside of India, we must assume that he is not prepared to co-operate further."

A two-member team of the ACU will visit India later this week reinforcing this message. "Gupta will either agree to be a formal witness or he won't. It's a personal call," Condon said.

The ACU has interviewed Gupta twice and he verbally confirmed all the allegations he made as outlined in the report last year by the Central Bureau of Investigation (CBI). These allegations have been denied by the individual players.

However, Condon said Gupta will now have to agree to be a witness in legal or disciplinary proceedings as his claims were at the core of evidence in the CBI report.

"It was not the only evidence but it was the principal evidence," Condon said. "Gupta's evidence is clearly central to the allegations. My concern is that, in addition to repeating the allegations, he has to stand up and be counted in disciplinary and legal proceedings".

The 39-year old Gupta, who used the alias 'John' in many of his dealings with players, was extensively quoted in the report by CBI. He claimed giving up bookmaking in 1998.

A former clerk with Syndicate Bank and with a gift for mathematics, he was so successful as a bookmaker that he was able to buy a house in Delhi's posh Defence Colony. But he has not been seen since the scandal broke and the tapes of his conversation with Hansie Cronje, former South African cricket captain, were published.

© PTI