Moody’s has put the ratings of Argentina-based YPF under review for possible downgrade and chopped also TGS. The agency placed YPF’s on review because of deteriorating economic conditions in Argentina and the decline in global commodity markets, and also because of concerns that higher government revenue needs and an unpredictable government policy framework could lead to tax and regulatory changes that will pressure YPF’s financial profile and operating performance. The affected ratings are the Baa2 global local currency rating and the Ba2 foreign currency bond rating on $225m bonds due in February 2009. Moody’s also downgraded TGS’ foreign currency debt ratings to B2 from B1, as it expects the company’s export revenues to halve in 2009 because of this year's drop in energy prices and an increase in export taxes. The outlook for TGS remains stable.