Moody's Investors Service early Tuesday downgraded its outlook for the European Union's debt rating to "negative" from "stable," raising the stakes in the eurozone crisis, dpa reported.
The change means that the rating agency is considering a lower rating for EU debt, from its current top ranked "Aaa" level.
Moody's said it had lowered its outlook because of the negative outlooks it has already issued to the sovereign ratings of key contributors to the EU budget: Germany, France, Britain and the Netherlands, which together contribute 45 per cent of the EU budget.
A lowered credit rating could lead to higher interest rates on public debt. That normally happens however only when several rating agencies give thumbs-down signals on their outlooks.