WRAPUP 5-UK unveils 50 bln pound credit crunch plan for banks

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By Matt Falloon and Christina Fincher

LONDON, April 21 (Reuters) - The Bank of England unveiled an ambitious plan on Monday to swap banks' risky mortgage assets for at least 50 billion pounds of government debt in the latest bid to spare Britain from the ravages of a global credit crunch.

Central banks everywhere have been desperately trying to get confidence back into markets, but despite eight months passing and billions spent, banks remain afraid to lend money because they don't know each others' exposure to bad U.S. home loans.

In Britain, the credit crunch has already taken down Northern Rock bank and concern is building over the financial system and the economy as new buyers are shut out of the housing market by cash-strapped lenders restricting mortgages.

Prime Minister Gordon Brown, whose popularity has slumped as voters lose faith in his handling of the economy, has made ending the credit crunch a priority, particularly as fears of a real estate crash have shot up in recent weeks.

His finance minister Alistair Darling said he would meet lenders on Tuesday to get them to do their bit -- pass on interest rate cuts and help people refinance their mortgages.

Speaking to reporters after the plan was announced, BoE Governor Mervyn King said the Special Liquidity Scheme (SLS) would not make things better overnight but would at least give banks access to a greater pool of cash.

The 50 billion pounds was just a start and there was no arbitrary limit, he said.