A British-led bid to crackdown on offshore tax evasion has been backed by 20 countries and territories, according to chancellor George Osborne.

The initiative, which sees those taking part automatically share information on the real owners of companies, was set up with Germany, France, Spain and Italy, but has been joined by Sweden, Gibraltar, Isle of Man and Montserrat, as well as other countries.

Those participating exchange data between tax and law enforcement agencies on company beneficial ownership registers and new registers of trusts in a bid to ensure more effective investigation of financial wrongdoing and tax-dodging.

Mr Osborne said the growing international group would deal a blow to tax evaders.

"Only a week after Britain launched this initiative with some of our closest European partners, it's gaining the international support that will be vital to make it truly effective," he said.

"I welcome the early commitment made by Gibraltar, Isle of Man and Montserrat to participate and call on all of the remaining Overseas Territories and Crown Dependencies to do likewise."

Countries joining the initiative include The Netherlands, Romania, Finland, Slovakia, Latvia, Croatia, Belgium, Ireland, Slovenia , Denmark, Malta, Lithuania, Cyprus, Bulgaria, Portugal, Estonia, Greece and Czech Republic.