London midday: Stocks near four-week low, supermarkets fall

- Markets at lowest in nearly four weeks- Russia said to be drawing up counter offer to US- Supermarkets fall after Kantar datatechMARK 2,841.55 -0.13%FTSE 100 6,674.07 -0.23%FTSE 250 16,448.94 -0.01% After a quiet start, UK stocks fell into the red by Tuesday lunchtime with retailers and banks dragging markets to their lowest in nearly four weeks.Geopolitical tensions in Ukraine continued to act as a drag on sentiment today with Russia reportedly drafting a counter offer to a US proposal to "de-escalate" the crisis. Washington has demanded that Moscow pull back its troops from Crimea and end attempts to annex the region.The FTSE 100 was trading 0.2% lower at 6,674 by midday, well below its intraday high of 6,714.99 reached early on. The index has not closed beneath this level since February 14th when it finished at 6,663.62."A bounce in Chinese equities after yesterday's rout wasn't enough to convince UK markets this morning, with equities selling off hard on the open," said Toby Morris, Senior Sales Trader at CMC Markets. Asian markets recovered overnight after a sell-off on Monday following data which showed that China recorded a surprise trade deficit of $22.98bn for February after exports slumped at an annual rate of 18.1%. Meanwhile, consumer price inflation slowed much more than forecast last month.In other news, the Bank of Japan refrained from increasing stimulus at its policy meeting, saying it expects a "moderate" recovery to continue. The central bank kept its current pace of stimulus in place ahead of sales tax increase next month. It also lowered its view of exports, but lifted its view on industrial output and investment.Supermarkets fall as competition intensifiesMorrison, Sainsbury and Tesco, which make up three of the so-called 'Big Four' UK supermarkets, were under pressure today after a Kantar survey showed that upmarket retailer Waitrose and discount grocers Aldi and Lidl continue to pose significant threats to competition. Sainsbury was the only one of the Big Four to hold market share year-on-year at 17% in the 12 weeks to March 2nd, but Morrison, Tesco and Wal-mart-owned Asda all recorded declines in share. Morrison and Tesco also saw a drop in actual sales, Kantar said.Meanwhile, investors were also reacting to this morning's British Retail Consortium data which showed that UK like-for-like retail sales unexpectedly fell by 1% in February.One retailer that was bucking the trend was sportswear chain Sports Direct ,which gained despite convening a shareholders meeting in order to push through a £65m bonus plan for founder Mike Ashley, after previous proposals were knocked back.Banking stocks including Barclays and RBS were under the weather as alleged forex manipulation continued to make headlines this morning amid a Treasury Select Committee grilling of Bank of England Governor Mark Carney.The share price of African Barrick Gold fell sharply after parent company Barrick Gold Corporation sold 41m shares, or 10% of the issued share capital, as it continues its "ongoing portfolio optimisation strategy".Inchcape rose after delivering record annual results as the car dealership enjoyed demand for luxury vehicles. The company reported a pre-exceptional pre-tax profit of £274.6m in the year through December 2013, up 11.2% on the prior year, as sales jumped 7.7% to £6.5bn.Johnson Matthey fell after Liberum Capital downgraded the stock to 'hold', while Aviva was a high riser after RBC Capital Markets raised its rating to 'sector performer'.FTSE 100 - RisersSports Direct International (SPD) 837.00p +3.46%Aviva (AV.) 521.50p +2.36%Aberdeen Asset Management (ADN) 384.30p +2.21%Reckitt Benckiser Group (RB.) 4,927.00p +1.80%International Consolidated Airlines Group SA (CDI) (IAG) 439.00p +1.36%CRH (CRH) 1,723.00p +1.23%Anglo American (AAL) 1,448.00p +1.05%Rolls-Royce Holdings (RR.) 1,054.00p +1.05%Capita (CPI) 1,137.00p +0.98%IMI (IMI) 1,464.00p +0.97%FTSE 100 - FallersBarclays (BARC) 235.05p -2.87%Severn Trent (SVT) 1,811.00p -2.27%Royal Bank of Scotland Group (RBS) 313.10p -2.10%Johnson Matthey (JMAT) 3,125.00p -1.98%Old Mutual (OML) 191.80p -1.94%Petrofac Ltd. (PFC) 1,331.00p -1.92%Morrison (Wm) Supermarkets (MRW) 229.70p -1.71%Pearson (PSON) 1,006.00p -1.57%WPP (WPP) 1,203.00p -1.47%Unilever (ULVR) 2,383.00p -1.28%FTSE 250 - RisersInchcape (INCH) 634.50p +3.17%Keller Group (KLR) 1,064.00p +2.80%Bank of Georgia Holdings (BGEO) 2,435.00p +2.79%Interserve (IRV) 641.50p +2.72%Pace (PIC) 471.00p +2.70%Carphone Warehouse Group (CPW) 336.70p +2.50%Senior (SNR) 295.30p +2.39%WH Smith (SMWH) 1,175.00p +2.26%Lonmin (LMI) 297.00p +2.06%Wetherspoon (J.D.) (JDW) 846.50p +1.99%FTSE 250 - FallersAfrican Barrick Gold (ABG) 260.80p -15.35%Fenner (FENR) 421.10p -5.63%Evraz (EVR) 57.85p -3.58%Computacenter (CCC) 693.00p -3.55%COLT Group SA (COLT) 140.00p -3.38%Renishaw (RSW) 2,059.00p -3.33%Kier Group (KIE) 1,749.00p -2.73%Cable & Wireless Communications (CWC) 52.00p -2.26%Berkeley Group Holdings (The) (BKG) 2,583.00p -2.16%Kenmare Resources (KMR) 14.95p -2.10%BC