Europe's weakest bank needs even more help

The rescue of Europe's weakest bank will cost more than expected.

Monte dei Paschi, the world's oldest operating bank, needs a $9.2 billion bailout. That's nearly twice what officials had predicted.

The Italian lender revealed the larger sum on Monday, citing an estimate from the European Central Bank.

Earlier this month, the lender cautioned it could run out of cash by May.

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