Among the nine countries to sign the treaty for fighting the offshore tax evasion were also Luxembourg, Austria and Singapore.

The treaty was signed on Wednesday and was an important mark in the international crackdown on privacy. It emerged that it may put a huge pressure on other offshore financial centers to agree to the treaty. Other six countries to sign the treaty were Belize, Estonia, Latvia, Nigeria, Saudi Arabia, and the Slovak Republic.

The treaty is multilateral convention on mutual administrative assistance, which is designed to assist the tax authorities in order to keep check on the tax cheats. The Secretary General of OECD Angel Gurria said that over 60 countries have agreed to sign or have already signed the convention.

He termed the moment as historic for fighting against the tax cheats. Tharman Shanmugaratnam, the Deputy Prime Minister of Singapore, said, "Singapore will work with our international partners to achieve that, so that Switzerland, Luxembourg, Singapore, Hong Kong and offshore jurisdictions like the British Overseas Territories move together".

Writing to the UK's Overseas Territories and Crown Dependencies, David Cameron has called on them to sign the treaty before the G8 summit to be held next month in Northern Ireland. Also, he said that they need to make sure that information exchange happens with efficacy for all.