Bankings stocks were providing a lift at midday with Barclays, RBS, Lloyds and HSBC all among the best performers, aided by euro optimism which has given a boost to sentiment. Tesco was also on the rise after US investor Warren Buffett stocked up on shares in the supermarket giant. Meanwhile, Essar Energy was the heaviest faller, losing over 11% as it continues to be hampered by problems in India, with its oil division being told on Tuesday that it is no longer eligible to benefit from a deferred tax payment scheme.Drugs giant AstraZeneca was also out of favour after the US Food and Drug Administration (FDA) announced that it wants more clinical data on its dapagliflozin treatment for type 2 diabetes in adults to assess the "benefit-risk" profile of the drug. Publishing group Pearson was lower despite upping its earnings guidance for 2011. Nomura said this morning that it expects organic growth rates to be less than 1% and flat in 2011 and 2012, respectively. The broker maintained its negative view on the stock, noting that the valuation is high at a price-to-earnings (FY12E) multiple of 14.6. Shares in Polymetal International, the newly-listed precious metals producer, fell after the firm admitted that annual gold production was flat at 443Koz in 2011, despite a 14% increase in the fourth quarter. Nomura did little to help the share price performance after initiating coverage of the stock with a reduce rating.FTSE 100 - RisersBarclays (BARC) 218.65p +8.73%Royal Bank of Scotland Group (RBS) 26.58p +7.00%Lloyds Banking Group (LLOY) 31.45p +6.30%International Consolidated Airlines Group SA (IAG) 163.30p +5.08%Evraz (EVR) 433.50p +4.18%Standard Chartered (STAN) 1,550.50p +4.13%Aviva (AV.) 338.20p +4.06%Man Group (EMG) 119.00p +4.02%Schroders (SDR) 1,419.00p +3.96%GKN (GKN) 212.10p +3.62%FTSE 100 - FallersEssar Energy (ESSR) 120.90p -11.23%Pearson (PSON) 1,206.00p -3.21%British Sky Broadcasting Group (BSY) 671.50p -2.61%AstraZeneca (AZN) 3,035.50p -2.44%Polymetal International (POLY) 1,113.00p -2.37%British American Tobacco (BATS) 2,899.00p -2.14%Rolls-Royce Group (RR.) 737.50p -1.60%GlaxoSmithKline (GSK) 1,445.50p -1.47%Diageo (DGE) 1,381.00p -1.46%ARM Holdings (ARM) 578.50p -1.11%NR