Analysts widely believe a decision will be forthcoming and that the outcome is unlikely to be positive.
Spain's credit rating currently sits one notch above 'junk' status.
Any downgrade would have severe consequences for the country, as some investors can't hold non-investment grade debt.
The news follows a weekend of protests against austerity measures across Spain and Portugal.
Thousands of Spaniards marched close to the parliament building in downtown Madrid peacefully for hours but police with batons eventually moved in to clear out those who remained.
Some protesters responded by throwing bottles and rocks and two people were hurt and 12 detained.
In neighbouring Portugal, tens of thousands took to the streets of Lisbon to peacefully protest against even deeper austerity cutbacks than Spain has imposed ( via skynews.com.au ).