Portugal's credit rating was downgraded one notch by Moody's on Tuesday as the resignation of the government raises concerns over financing requirements.

The rating agency cut Portugal's long-term government bond ratings from A3 to Baa1 and placed the rating on review for further possible downgrade. Moody's said the uncertain political outlook following the resignation of the Portuguese government; challenges to secure short- and medium-term funding and revisions to the estimates for the budget