Shares in Countrywide Financial plunged more than 13% after an analyst said Bank of America should walk away from its agreed $4bn deal to acquire the troubled US home mortgage lender. Financial Times

Paul Miller, an analyst at Friedman, Billings, Ramsey, said in a note to clients that BofA should 'completely walk away' from the deal.

Otherwise, he said, the bank could face $20bn to $30bn in writedowns on Countrywide’s home loans after it closes the acquisition this year.

If it does not walk away from the deal, BofA will probably renegotiate its takeover price for Countrywide down to $2 a share or less, Miller wrote.