In a Thursday bond auction, yields rose for Spain, Portugal and Italy as investors took on 2.4 billion euros in 10-year and 15-year bonds.

Traders said that the auction was smooth amid overall light trading, although investors required a high yield that revealed their nervousness over the state of Spain’s economic health, according to a Reuters report. A Paris-based trader at a major investment bank said that the yield widened from six to eight basis points just after the auction, something he said was common in Spanish auctions.

Average yields for Spain were between 80 and 140 basis points higher than its bonds offered in October and November sales, and on Wednesday the10-year yield was up more than 20 basis points in December. More than 70% of the bidders, it was said, were non-resident investors.

Meanwhile,Greece faced a possible downgrade as Moody’s Investors Service on Thursday put that country’s sovereign foreign currency credit rating on review. Even though the rating agency acknowledged that Greece had made “significant” progress in putting into effect a fiscal consolidation, there is concern that Athens may be unable to bring its debt down to sustainable levels.

The rating agency issued a statement that said in part, “Moody's review will focus on the factors, namely nominal growth and fiscal consolidation, that will drive the country's debt dynamics over the next few years.”

Currently, Greece carries a Moody’s rating of Ba1, the highest junk status. That rating is equivalent to Standard & Poor’s rating of BB+. Fitch Ratings still rates Greece at investment grade status of BBB-.