Royal Bank of Scotland Group topped the risers on the FTSE 100 on Wednesday after ratings agency Fitch said that a break-up of the state-backed UK lender into a 'good' and 'bad' bank is increasing unlikely as the costs would outweigh the benefits. Part-nationalised counterpart Lloyds was also making gains today.Banking peer Barclays also gained despite confirming reports Financial Director Chris Lucas will step down this week for health reasons. Lucas was due to depart the company on February 28th 2014 but said he had to bring the date forward.Pharmaceutical group GlaxoSmithKline rose after JPMorgan Cazenove raised its recommendation on the shares to 'neutral'. The broker said that the upside from upcoming catalysts balances out earnings risk.Leading the downside was housebuilder Persimmon, pulling back after an impressive +50% rise in the share price since the start of the year (ahead of today).ENRC was also a heavy faller as it reported a decline in first-half revenue after trading was hit by poor pricing environment, higher finance costs, increased effective tax rate and impairments at Boss Mining. Sector peers Rio Tinto and Anglo American were also lower today.Glencore Xstrata however was bucking the trend, trading higher after reporting increases in copper, gold and coal production in the first half, offset partly by a slight fall in zinc output.Oil major Shell was trading lower after going ex-dividend, though downside was limited after Barclays Capital upgraded its rating on the stock to 'overweight' saying that it remains "our preferred 'MegaCap' stock". Beverage groups Diageo and SABMiller were also down after going ex-dividend today.FTSE 100 - RisersRoyal Bank of Scotland Group (RBS) 338.90p +1.77%Aviva (AV.) 405.70p +1.76%Weir Group (WEIR) 2,286.00p +1.69%Schroders (SDR) 2,461.00p +1.44%Lloyds Banking Group (LLOY) 76.86p +1.43%Burberry Group (BRBY) 1,594.00p +1.27%Old Mutual (OML) 198.50p +1.22%Legal & General Group (LGEN) 200.00p +1.21%ARM Holdings (ARM) 902.00p +1.18%Tullow Oil (TLW) 1,070.00p +1.13%FTSE 100 - FallersPersimmon (PSN) 1,186.00p -3.34%Eurasian Natural Resources Corp. (ENRC) 229.40p -3.00%Rio Tinto (RIO) 3,205.00p -1.78%Pearson (PSON) 1,324.00p -1.71%AstraZeneca (AZN) 3,255.50p -1.69%Anglo American (AAL) 1,546.50p -1.65%Rexam (REX) 506.50p -1.65%easyJet (EZJ) 1,323.00p -1.56%GKN (GKN) 348.80p -1.25%Marks & Spencer Group (MKS) 467.30p -1.12%BC