Pressure is mounting on Giles Clarke, chair of the England and Wales Cricket Board (ECB), after he admitted that it was a mistake to enter into a five-year business agreement with American billionaire, Sir Allen Stanford.

It follows an announcement from the United States Securities and Exchange Commission (USSEC) on 17 February that Stanford had been charged over allegations of a US$8bn (£5.6bn) investment fraud. The ECB and the West Indies Cricket Board (WICB) have suspended negotiations with Stanford "concerning a new sponsorship deal", although Clarke insists that he will not resign over the matter.

When asked whether it was a mistake to sign a five-year agreement with Stanford, which includes an annual Twenty20-for-20 match, a quadrangular tournament and the English Premier League, Clarke said: "We had the best of intentions, so yes." "We have a situation where a court case has been filed," he continued. "The matter is therefore sub judice. We also have contractual rights with this particular situation.

"At the moment, all of the obligations with regard to the game that was played have been met and all of the various people who were expected to do various things for that match have received their remuneration, as far as I am aware." Clarke also revealed that the ECB carried out due diligence before signing the deal with Stanford, while a proposed four-team tournament featuring New Zealand and Sri Lanka this summer at Lord's may no longer go ahead.

However, Lord Marland, the former Conservative Party treasurer who recently withdrew his bid to oust Clarke as ECB chair in a forthcoming election, told the Guardian that in any other company, heads would roll over such an issue. "The ECB has walked into the open arms of a man who has now been charged with fraud," he said. "What due diligence was carried out? The picture of Clarke, Collier and Stanford standing behind all those dollars will haunt English cricket for a long time."

Linda Chatman Thomsen, director of the USSEC's Division of Enforcement, said: "As we allege in our complaint, Stanford and the close circle of family and friends with whom he runs his businesses perpetrated a massive fraud based on false promises and fabricated historical return data to prey on investors. "We are moving quickly and decisively in this enforcement action to stop this fraudulent conduct and preserve assets for investors."