UK stocks were trading within a narrow range on Thursday as investors refrained from taking on too much risk ahead of the European Central Bank (ECB) policy meeting, which has the potential to spark volatility across financial markets worldwide.The FTSE 100 was trading just 0.03% higher at 6,719 by around noon, with less than 30 points separating its intraday low (6,706.81) and high (6,733.96).The Bank of England announced at midday that it had left its Bank Rate at 0.5% and its asset purchase programme at £375bn, as expected by the market.While the ECB is broadly predicted to leave policy unchanged, there is a risk of a surprise at the meeting after recent hints by ECB president Mario Draghi that the bank could soon embark on 'full-blown' quantitative easing (QE).Analyst Craig Erlam from Alpari UK said that while the consensus view is for no stimulus from the ECB on Thursday, "there is a growing expectation in the markets that the central bank will announce its first QE package early next year and therefore investors will be monitoring comments closely for hints on when that could happen".The closely-watched US employment report due on Friday is also prompting an element of caution on the markets. Data is forecast to show that 230,000 non-farm jobs were added in November, up from 214,000 in October, though the jobless rate is expected to remain unchanged at 5.8%.Easyjet and TUI Travel impressBudget airline Easyjet was flying high after saying that passenger numbers increased by 3.1% to 4,386,296 in November against the same month in 2013.Travel tour operator TUI Travel impressed after meeting expectations with a 4% rise in annual profits as the company painted a positive outlook for the winter and upcoming summer season ahead of its planned merger with parent group TUI AG.Sage's shares were extending gains after the accountancy software group impressed the market with its annual results on Wednesday, with the stock given a boost by target price upgrades at both Citigroup and Credit Suisse.A reduction in risk appetite was hitting the miners with Anglo American, Rio Tinto, Fresnillo, Randgold Resources and BHP Billiton trading lower.A number of heavyweight stocks were lower after going ex-dividend, including London Stock Exchange, Severn Trent, Next, Whitbread, Land Securities and RBS on the FTSE 100.FTSE 250-listed Debenhams also went ex-dividend, though the retail stock was also under pressure after a downgrade from 'hold' to 'sell' by N+1 Singer.Betfair shares jumped after the online betting and gaming operator delivered a 26% jump in half-year revenue and announced a £200m capital return. The company also increased its targeted dividend payout ratio to approximately 50% of earnings.Packaging company DS Smith was also higher after pre-tax profit soared 45% in the first half of 2014, courtesy of strong performances across the board.Market MoverstechMARK 2,962.56 +0.75%FTSE 100 6,718.81 +0.03%FTSE 250 15,903.13 +0.58%FTSE 100 - RisersSage Group (SGE) 451.10p +6.87%TUI Travel (TT.) 446.70p +4.20%Persimmon (PSN) 1,590.00p +3.25%CRH (CRH) 1,573.00p +2.48%Royal Mail (RMG) 407.70p +2.44%Burberry Group (BRBY) 1,670.00p +2.27%Unilever (ULVR) 2,726.00p +1.87%Hargreaves Lansdown (HL.) 1,010.00p +1.76%easyJet (EZJ) 1,697.00p +1.74%Carnival (CCL) 2,761.00p +1.58%FTSE 100 - FallersAnglo American (AAL) 1,280.00p -3.03%Fresnillo (FRES) 720.50p -2.31%Rio Tinto (RIO) 2,945.50p -2.18%Severn Trent (SVT) 1,989.00p -1.83%BG Group (BG.) 920.80p -1.67%Randgold Resources Ltd. (RRS) 4,259.00p -1.66%Tullow Oil (TLW) 414.30p -1.61%BHP Billiton (BLT) 1,495.00p -1.55%Antofagasta (ANTO) 729.50p -1.29%BP (BP.) 431.40p -1.25%FTSE 250 - RisersBetfair Group (BET) 1,459.00p +6.65%Smith (DS) (SMDS) 306.00p +6.10%Alent (ALNT) 352.40p +3.77%Bellway (BWY) 1,927.00p +3.60%Redrow (RDW) 291.20p +3.59%Taylor Wimpey (TW.) 137.10p +3.47%Crest Nicholson Holdings (CRST) 371.90p +3.39%Barratt Developments (BDEV) 474.10p +3.31%NMC Health (NMC) 485.10p +3.21%Bovis Homes Group (BVS) 896.50p +2.81%FTSE 250 - FallersFerrexpo (FXPO) 64.00p -6.71%Debenhams (DEB) 70.70p -3.42%De La Rue (DLAR) 517.00p -3.36%EnQuest (ENQ) 47.50p -3.06%Premier Oil (PMO) 193.30p -3.01%Electrocomponents (ECM) 206.00p -2.74%Hunting (HTG) 560.00p -2.69%Greencore Group (GNC) 289.50p -2.59%Vedanta Resources (VED) 681.50p -2.57%Cairn Energy (CNE) 163.20p -2.57%