London midday: Stocks hit by political uncertainty, economic data

Political uncertainty in Europe, disappointing economic figures from China and nervousness ahead of some key 'risk events' later this week prompted a sell-off on the FTSE 100 on Wednesday morning.Resignations of both the Portuguese Finance Minister and Foreign Minister over the last few days have sparked concerns all over the Eurozone, as anti-austerity rallies gather support. Portugal's 10-year bond yields have now surged above 8.0% for the first time since November."It's looking increasing likely that we'll see early elections in Portugal," said Market Analyst Craig Erlam from Alpari. "This is far from ideal for the Eurozone at a time when it has benefitted from not being centre stage for a few months, and only a couple of months before the elections in Germany. The last thing Angela Merkel needs in the run up to the election is more bailout and austerity discussions with a new Portuguese government."Meanwhile, activity in China's services sector remained sluggish in June with the official non-manufacturing purchasing managers' index (PMI) falling from 54.3 to a nine-month low of 53.9 in June. Meanwhile, separate data published by HSBC/Markit showed that the services PMI edged up to 51.3 from May's reading of 51.2, but the rate of expansion in new orders was the weakest in 55 months.The Eurozone services PMI also disappointed, falling from 48.6 to 48.3 in June (forecast: no change). However, one bright spot came from the UK where economic data continues to impress: the UK services PMI rose to 56.9 points, its best reading since March 2011, from 54.9 in the month before (forecast: 55.0). Markets nervous ahead of 'risk events'The US services PMI and ADP employment report are due out later, in addition to US jobless claims which are being released one day early due to the Independence Day holiday tomorrow.Meanwhile, markets are also looking ahead to the European Central Bank and Bank of England (BoE) which are to reveal their latest policy decisions on Thursday afternoon with all eyes turning to Mark Carney as he heads up his first meeting as BoE Governor.However, the big event of the week is likely to be the US non-farm payroll report due out on Friday with investors waiting nervously given that a positive surprise could prompt the Federal Reserve to move more quickly to scale back its stimulus programme.FTSE 100: Miners, ex-divs and financials fallConcerns over a slowdown in China were weighing heavily on mining stocks this morning with Anglo American, Vedanta and Glencore Xstrata among the worst performers. Burberry was trading firmly in the red after going ex-dividend, along with heavyweights British Land and Babcock.Banking group Barclays was also lower after S&P cut its credit rating by one notch, saying that its debt holders "face heightened credit risk owing to the industry's tighter regulation, fragile global markets, stagnant European economies and rising litigation risk stemming from the financial crisis".Heading the other way was Tullow Oil, rising strongly after a strong first-half operational update. The company said that revenue totalled $1.3bn, slightly ahead of the $1.2bn reported the year before.Sector peer Shell however fell despite revealing upbeat drilling results from an exploratory well in the Gulf of Mexico. The well, located 75 miles offshore in the De Soto Cayon Block 393 in 7,446 feet (ft) of water, encountered more than 500ft of net oil pay after being drilled to a total depth of 26,385ft.FTSE 250:Spirent Communications shares tumbled after the technology testing company revealed weaker-than-expected revenues for the second quarter. Group revenue is expected to fall by $26m to $92.7m for the three months to the end of June after weak orders in the first quarter, Spirent said in a trading statement. Pizza delivery firm Domino's Pizza was also down despite reporting 11.7% sales growth in the second quarter. The company said that the results come on top of "very strong comparatives" from last year.Halfords, HomeServe and TalkTalk were lower after going ex-dividend.FTSE 100 - RisersTullow Oil (TLW) 1,062.00p +2.81%ARM Holdings (ARM) 818.50p +1.36%Next (NXT) 4,662.00p +0.63%G4S (GFS) 225.70p +0.49%Kingfisher (KGF) 354.20p +0.45%London Stock Exchange Group (LSE) 1,400.00p +0.29%Bunzl (BNZL) 1,318.00p +0.23%Severn Trent (SVT) 1,688.00p +0.18%Pearson (PSON) 1,194.00p +0.17%Serco Group (SRP) 666.50p +0.15%FTSE 100 - FallersAnglo American (AAL) 1,215.50p -5.04%CRH (CRH) 1,288.00p -4.87%Vedanta Resources (VED) 995.00p -4.23%Glencore Xstrata (GLEN) 264.95p -4.00%Burberry Group (BRBY) 1,349.00p -3.99%Weir Group (WEIR) 2,078.00p -3.75%BHP Billiton (BLT) 1,653.50p -3.36%Fresnillo (FRES) 888.50p -3.27%Standard Chartered (STAN) 1,417.50p -3.14%Barclays (BARC) 274.65p -2.95%FTSE 250 - RisersPZ Cussons (PZC) 379.70p +1.80%Countrywide (CWD) 537.00p +1.32%Workspace Group (WKP) 415.40p +1.02%Micro Focus International (MCRO) 717.50p +0.77%BH Macro Ltd. EUR Shares (BHME) € 21.07 +0.77%Menzies(John) (MNZS) 705.00p +0.71%Fisher (James) & Sons (FSJ) 986.00p +0.61%Greggs (GRG) 412.80p +0.41%Synergy Health (SYR) 1,122.00p +0.36%Utilico Emerging Markets Ltd (DI) (UEM) 171.50p +0.35%FTSE 250 - FallersSpirent Communications (SPT) 122.00p -9.23%Domino's Pizza Group (DOM) 623.00p -6.88%Homeserve (HSV) 268.90p -5.85%Hochschild Mining (HOC) 155.90p -5.52%De La Rue (DLAR) 933.50p -5.23%Fenner (FENR) 303.10p -3.99%UBM (UBM) 639.00p -3.91%Evraz (EVR) 101.10p -3.90%Essar Energy (ESSR) 123.10p -3.75%TalkTalk Telecom Group (TALK) 220.40p -3.59%