Spain has lost its last triple-A credit rating with the major rating agencies, following a downgrade from Moody's.
The agency downgraded Spanish debt by one level to Aa1, following similar moves by Fitch and Standard & Poor's earlier this year.
Moody's said the downgrade reflected the "considerable deterioration" in Spain's public finances.
Spain has been among the European countries to introduce tough austerity measures to tackle the problems in its public finances.
Earlier this week Spanish unions held a general strike in protest against the cuts.