UK premier Gordon Brown said he plans to secure an international agreement to help clamp down on tax avoidance.

Speaking in the UK parliament, Mr Brown said it is "possible to get an international agreement for the exchange of information in relation to tax cases", but said the government was first awaiting the outcome of UBS tax evasion investigation in the US. He did not explicitly name the bank, referring only to a case of Swiss tax evasion under examination in US courts.

US prosecutors are expanding their investigation into UBS for allegedly helping wealthy US citizens evade taxes and have given the Swiss bank “several weeks” to hand over US client names or face indictment, media reports said last month.

An international tax agreement could lead to more information sharing about the tax-cutting strategies of corporations.

Mr Brown was speaking after Nick Clegg, leader of the UK's third largest party, the Liberal Democrats, challenged him about the findings of an investigation by UK newspaper The Guardian into the scale of the "tax gap" - the amount of money being lost to the exchequer through companies using complex strategies to cut their tax liabilities.

Mr Clegg accused UK firms of using loopholes to avoid paying £14 billion (about $26 billion) in corporation tax.  He said Mr Brown had "one rule for fat cats and another rule for everyone else" and asked why Brown was not cracking down on tax avoidance. "Instead of going on about British jobs for British workers, isn't it time to go on about British taxes for British companies?" Mr Clegg asked.

"That would be the way that we could move forward our proposals, that we could have both the exchange of information on tax and clamp down on these tax evaders,"said Mr Brown.