Banks in bailed-out Portugal need an extra 8 billion euros ($10 billion) in capital, based on conservative tests of their financial health, Moody's Investors Service said on Wednesday.
Pepa Mori, the rating agency's lead analyst for Portuguese banks, said non-performing loans had risen more than expected because of the country's deepening recession, justifying a gloomier set of assumptions.
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"We have identified, according to our stress tests, capital needs of 8 billion euros for the Portuguese system as a whole. This is according to our more conservative scenario," she told Reuters.
That would be 2 billion euros more than what remains of the funds earmarked for recapitalizing the banks in Portugal's 78-billion-euro EU/IMF bailout.
Kathrin Muehlbronner, an analyst with Moody's sovereign risk group, said last week's rejection by the constitutional court of some austerity measures was a setback for Portugal's deficit reduction program, but it was premature to judge its full implications.
"It is probably a bit too early to make definite statements on whether in September Portugal can regain market access," she told Reuters. "Lots of things can happen in a few months' time."
The government launched its first bond since the 2011 bailout in January and has been looking at further issues to regain full access to financial markets before the bailout ends in mid-2014. Portugal's financing needs are fully covered by the bailout until at least September.
"We have to see how that is taken up by investors, but I think that everyone is aware - and surely the government is aware - of the constraints that they face," Muehlbronner said.
Portugal's bailout had allocated 12 billion euros for bank recapitalization. About half of that money has been used so far.
"What is positive is we know that 6 billion euros is available to recapitalize the banking system in case of need," Mori said.
Asked whether banks could obtain financing via debt issuance after Banco Espirito Santo returned to the bond market late last year, Mori said it could not be ruled out.
"It's true that the appetite for seeking capital in the market seems to be limited, but it has happened, so we cannot say that there is no possibility at all for banks to obtain capital in the markets."