BUDAPEST, Hungary - European finance ministers will try to work out the size and terms of a rescue loan for Portugal at their two-day meeting in Hungary - but uncertainty persists over how much the caretaker government in Lisbon can offer in return.

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Portugal submitted an official request for help to the European Commission, the EU's executive, Thursday evening, officially kicking off negotiations for a bailout that had been anticipated for months.

Finance Minister Fernando Teixeira dos Santos now has to convince his 16 eurozone counterparts on Friday and Saturday that Lisbon has the authority to implement reforms and budget cuts designed to get the country's economy back on track.