Stocks jumped strongly on Tuesday morning following a decent finish on Wall Street the night before on the back of easing concerns about a potential US strike on Syria.US benchmarks rose by an average 1% on Monday after Russian Foreign Minister Sergei Lavrov urged Syria to place any chemical weapons they may have under international control in an attempt to avoid action from the States. The news that Syrian counterpart Walid Muallem apparently welcomed the proposal has given investor sentiment a large boost this morning, especially given that President Barack Obama said that he would put air strikes on hold if Bashar al-Assad's government follows the initiative.Market Analyst Craig Erlam from Alpari said that a US-led military response had looked "inevitable" until now, but reports that Syria has welcomed Russia's suggestion "could be a game changer, although at this stage there has not been confirmation that Assad would approve such a move".Supporting stocks further this morning was a continuing improvement in economic data from China with the third-quarter outlook for the Asian powerhouse continuing to brighten. Industrial output, fixed-asset investment and retail sales strengthened during the month of August, with all three economic indicators rising by more than expected.FTSE 100: Miners, airlines jump early onMining stocks were benefitting from increased risk appetite this morning despite metals prices taking a hit. Glencore Xstrata was leading the upside on London's blue-chip index after lifting its synergy target - following its merger - to at least $2bn next year as the miner vowed to cut costs and improve operational efficiency.Resource peers Rio Tinto and Anglo American were also higher early on.Airline groups IAG and easyJet were flying higher this morning as crude continued to pull back from its recent highs as fears over turmoil in the Middle East ease. Elevated oil prices have pressured both stocks over the last few weeks on concerns over the knock-on effects to jet fuel costs.Rolls-Royce gained after scoring a $175m contract with Asia Gas Pipeline (AGP) for services on a natural gas pipeline in Kazakhstan.Leading the downside was Costa and Premier Inn owner Whitbread after seeing sales growth slow down from 13.8% in the first quarter to just 10.8% in the second as the hot summer weather hit demand at its coffee shops.Drinks giant SABMiller was on the climb this morning after HSBC upgraded the stock to 'overweight', while consumer products group Unilever was lifted by Deutsche Bank to 'buy'.FTSE 250: Ashmore jumps, Oxford Instruments slumpsRecord subscriptions helped emerging markets asset manager Ashmore to drive strong net inflows into its funds in the year to June, giving the share price a boost this morning. Strong net inflows of $13.4bn led to a 22% increase in assets under management (AuM) to $77.4bn during the year, with average AuM rising 13%.Oxford Instruments was a heavy faller after saying that while growth in the order intake rate in Industrial Products and third party Service is encouraging, slowness in R&D markets in the Western economies means that the year is likely to be more second half-weighted. FTSE 100 - RisersGlencore Xstrata (GLEN) 335.95p +4.56%International Consolidated Airlines Group SA (CDI) (IAG) 318.60p +4.29%easyJet (EZJ) 1,307.00p +3.16%Royal Bank of Scotland Group (RBS) 350.00p +2.94%Rio Tinto (RIO) 3,215.50p +2.72%Aberdeen Asset Management (ADN) 379.00p +2.65%Standard Chartered (STAN) 1,493.00p +2.58%GKN (GKN) 356.40p +2.50%Prudential (PRU) 1,164.00p +2.37%Lloyds Banking Group (LLOY) 78.55p +2.31%FTSE 100 - FallersWhitbread (WTB) 3,094.00p -3.79%GlaxoSmithKline (GSK) 1,581.00p -3.60%BG Group (BG.) 1,207.50p -0.78%Eurasian Natural Resources Corp. (ENRC) 223.20p -0.71%Vodafone Group (VOD) 209.90p -0.24%Fresnillo (FRES) 1,267.00p -0.16%Amec (AMEC) 1,049.00p -0.10%Randgold Resources Ltd. (RRS) 4,913.00p -0.02%FTSE 250 - RisersAshmore Group (ASHM) 380.20p +4.77%Bumi (BUMI) 220.00p +4.17%Thomas Cook Group (TCG) 155.70p +3.87%Lonmin (LMI) 354.80p +3.71%Fenner (FENR) 383.50p +3.40%Inchcape (INCH) 631.00p +3.10%Supergroup (SGP) 1,237.00p +3.08%Mitchells & Butlers (MAB) 471.80p +2.99%Fidessa Group (FDSA) 2,224.00p +2.87%COLT Group SA (COLT) 116.20p +2.83%FTSE 250 - FallersOxford Instruments (OXIG) 1,425.00p -5.63%PayPoint (PAY) 1,060.00p -3.99%African Barrick Gold (ABG) 178.00p -3.05%Rank Group (RNK) 155.00p -2.58%Centamin (DI) (CEY) 46.05p -1.85%Daejan Holdings (DJAN) 3,880.00p -1.65%BH Macro Ltd. EUR Shares (BHME) € 20.78 -1.28%Alent (ALNT) 370.00p -1.25%BH Macro Ltd. GBP Shares (BHMG) 2,137.00p -1.16%BH Macro Ltd. USD Shares (BHMU) 20.23 -1.08%BC