A TEAM from the International Monetary Fund will ask Britain's biggest banks for detailed information this week as it assesses the health of lenders in five European countries.
The IMF is checking Britain's banks before wider so-called stress tests by the European Union, three industry sources said.
A separate source said the team was expected in Sweden next month or early March.
The IMF said late on Tuesday that it is conducting what it called "routine" stress tests of financial systems in Britain, Sweden, the Netherlands, Germany and Luxembourg.
The European Union has come under pressure after finding only a small capital shortfall among banks last year, just before spiralling problems at banks forced an international bail-out of the Irish government.
The IMF's Financial Sector Assessment Programmes, or FSAPs, were made mandatory in September for 25 "systemically important" countries, in a move to forestall a repetition of the global credit crisis.
Established in 1999, they are "a comprehensive and in-depth analysis of a country's financial sector", according to the IMF website.
The test of Britain's top banks, including HSBC, Barclays and Lloyds Banking Group, is expected to take several weeks, sources said. The tests in all five countries will be conducted in the first quarter of this year, the IMF spokesman said.
The European Banking Authority will similarly test its financial sector in a tougher repeat of last year's health