The England and Wales Cricket Board has threatened to take legal action against Pakistan Cricket Board chairman Ijaz Butt unless he apologises for accusing England of losing a game.
Butt said he had heard from bookmakers that England had been paid to lose Friday's third one-day game at The Oval.
England, who lost the game by 23 runs, has denied the allegations, The BBC reports.
ECB chief David Collier said: "We are looking for an apology. If it does not come we'll look at other options. Clearly we will seek advice but there are quite strong laws of defamation. You can't impugn someone's integrity without having proper evidence."
"To date I can say that we have received zero evidence of anything having influenced any England player," he added.
The International Cricket Council is also looking into Pakistan's performance in last week's one-day game at The Oval after receiving reports about "scoring patterns" during their innings.