Gordon Brown believes the large economies are close to agreeing a global tax on banks which would cost the financial sector billions of pounds a year - but he played down expectations of a final deal at the next G20 meeting in June.
Brown, who held talks with Angela Merkel, German chancellor, last week, said the scene was set for a -"global responsibility levy", the Financial Times reports.
He said Britain, France and Germany were now broadly agreed on the need for a levy, and he hoped the US would come on board.
"Britain, France and Germany have talked about what we can do together," he said. "We are agreed on the need for a common basis."
France and Germany last week jointly backed an internationally co-ordinated levy.
TESCO HAS REVEALED it expects to gain a 10% share of Britain's financial services market, making it roughly as big as Abbey and more than half the size of Barclays, the Daily Mail reports.
The supermarket giant, which already sells insurance and some savings products, plans to launch mortgage deals by the end of this year, with a current account to follow in 2011.
Senior executives have never before put down a marker for the group's financial services ambitions.
Tesco has about 20 million shoppers each week and plans to capitalise on public disappointment in traditional banks
We might be a bit bigger than 10% in some areas and a bit smaller in others, but that is roughly where we expect to end up,' said a top Tesco source.
Though the company plans to build its financial services presence largely by exploiting demand from its 15 million Clubcard holders, it has about 20 million shoppers each week and expects to pick up business from those who have lost faith in traditional banks.
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