Spurred on by the ratings agency’s cut, six leading parties hurriedly resumed talks to agree on a 2012 budget to contain Belgium’s high debt and deficit, two more reasons why the country has come under increasing pressure from financial markets this week.

In a sign that financial contagion is spreading across Europe, the agency cut Belgium’s credit rating from AA+ to AA, a move coming two days after Germany fared surprisingly poorly at a bond auction.

Belgium has been without a permanent government for 530 days, as a series of negotiators has struggled without success to bridge the country’s divide between its French and Dutch speakers.

“In our opinion, protracted political uncertainty remains a risk to its creditworthiness,” the ratings agency said.