The Organisation for Economic Cooperation and Development (OECD) on Thursday named two lists of nations - one black and one grey - that were not doing enough to help crack down on tax cheats and excessive bank secrecy.

The lists were made public as G-20 leaders from rich and developing nations declared at their London summit that the age of banking secrecy was over and that they would no longer tolerate shady havens draining away badly needed tax revenue.

The grey list comprises 38 countries - including Switzerland and Monaco - that say they have 'committed to the internationally agreed tax standard, but have not yet substantially implemented' it.

Four nations that have not yet agreed to change banking secrecy practices were put on a black list for being uncooperative tax havens. They are the Philippines, Uruguay, Costa Rica and the Malaysian territory of Labuan.

The announcement reflects mounting concern that banking secrecy in tax havens has helped worsen the economic crisis by disguising the true value of some global assets.

The OECD estimates that anywhere between US$1.7 trillion and US$11.5 trillion of assets are held offshore globally.

Reacting on Friday to being on the grey list, the Swiss finance minister issued a statement saying that 'President Hans-Rudolf Merz regrets this procedure'.

'The list does not specify the criteria on the basis of which it was drawn up. Switzerland is not a tax haven.'

Luxembourg's Prime Minister, Mr Jean-Claude Juncker, said: 'I find the treatment of certain states to be incomprehensible. We will negotiate double-taxation agreements. When we do that we will disappear from this list.'

Read the full report in Saturday's edition of The Straits Times.