- Moody's downgrades six nations, three ratings outlooks cut to negative.- Miners provide a drag in London.News that Moody's had downgraded its ratings on several Eurozone nations and revised its outlook on others, including the UK, weighed on the Footsie in early trading on Tuesday. Miners were among the worst performers as the outlook for the global economy took another turn for the worse.Ratings agency Moody's Investors Service last night downgraded six European sovereigns, Italy, Malta, Portugal, Slovakia, Slovenia and Spain, "in order to reflect their susceptibility to the growing financial and macroeconomic risks emanating from the euro area crisis and how these risks exacerbate the affected countries' own specific challenges," Moody's said.Meanwhile, Moody's revised is outlook on the Aaa ratings of the UK, Austria and France to negative."The negative outlooks reflect the presence of a number of specific credit pressures that would exacerbate the susceptibility of these sovereigns' balance sheets, and of their ongoing austerity programmes, to any further deterioration in European economic conditions and financial landscape," the statement said.MINERS PROVIDE A DRAG EARLY ONMiners took a hit in the opening hour with Rio Tinto, Xstrata, Anglo American and BHP Billiton among the heaviest fallers. BHP and Rio both approved a major investment to ramp up production at the Escondida copper project in Chile worth over $4.5bn, it was announced this morning. BHP also announced a 17% increase in the mineral resources and a 25% increase in the ore reserves at Escondida following successful brownfield exploration and accelerated in-fill development drilling programmes.Power systems developer Rolls-Royce rose after bagging a contract from Fiji's national airline, Air Pacific, a new customer for the UK company.On the FTSE 250, paper and packaging group Mondi was in demand after saying underlying profit for the fourth quarter of 2011 is expected to be on a par with the corresponding quarter of 2010.Specialist healthcare firm BTG nudged higher after it announced that Chief Financial Officer Rolf Soderstrom has decided to stay put and will no longer leave the company at the end of its fiscal year.AIM-listed oil and gas firm San Leon Energy jumped over 8% after saying that drilling at one of its sites has encountered "continuous gas shows".Shares in Yell Group fell 13% after revenues continued to fall in the final three months of 2011. The news of a 15.1% year-on-year fall in revenues will further depress investors, already worried about the company's £2.6bn debt mountain that it managed to restructure between December and January. BCFTSE 100 - RisersBunzl (BNZL) 895.50p +1.99%Polymetal International (POLY) 1,112.00p +1.09%Man Group (EMG) 132.50p +0.99%ARM Holdings (ARM) 580.50p +0.87%Wolseley (WOS) 2,337.00p +0.82%International Consolidated Airlines Group SA (IAG) 176.50p +0.68%BAE Systems (BA.) 321.90p +0.59%ICAP (IAP) 370.00p +0.52%BP (BP.) 498.60p +0.52%Evraz (EVR) 426.50p +0.38%FTSE 100 - FallersRio Tinto (RIO) 3,763.00p -2.15%Marks & Spencer Group (MKS) 343.50p -1.52%Vodafone Group (VOD) 172.30p -1.20%Xstrata (XTA) 1,200.00p -1.07%Anglo American (AAL) 2,787.50p -1.05%British Land Co (BLND) 490.00p -1.05%BHP Billiton (BLT) 2,062.00p -0.98%Royal Bank of Scotland Group (RBS) 27.85p -0.89%Lloyds Banking Group (LLOY) 34.98p -0.88%National Grid (NG.) 633.50p -0.86%FTSE 250 - RisersCarpetright (CPR) 602.00p +4.15%Mondi (MNDI) 558.00p +4.10%Yule Catto & Co (YULC) 212.80p +2.55%Shanks Group (SKS) 108.00p +2.27%Rank Group (RNK) 140.90p +2.10%Perform Group (PER) 263.80p +2.05%Misys (MSY) 296.20p +2.03%Grainger (GRI) 107.70p +1.60%Hansteen Holdings (HSTN) 76.15p +1.53%CSR (CSR) 236.10p +1.50%FTSE 250 - FallersRotork (ROR) 1,905.00p -3.50%Aquarius Platinum Ltd. (AQP) 144.60p -3.15%Howden Joinery Group (HWDN) 112.20p -2.60%Galliford Try (GFRD) 500.00p -2.34%Hochschild Mining (HOC) 507.50p -1.93%Kier Group (KIE) 1,433.00p -1.92%Kenmare Resources (KMR) 57.40p -1.88%Cable & Wireless Communications (CWC) 37.35p -1.76%Jupiter Fund Management (JUP) 242.80p -1.74%Go-Ahead Group (GOG) 1,290.00p -1.68%