Telecommunication stocks were leading for a second day running on Wednesday as BT Group took its campaign for the right to offer the Sky Sports channels on YouView set-top boxes to a competition tribunal.BHP Billiton led oil and gas shares higher after reporting a 31% rise in first-half profit after achieving cost savings. Jefferies issued a 'buy' rating following the results, saying BHP is "one of our top picks in the sector".On the downside, the Aerospace and Defence sector slumped, including Rolls-Royce as Citigroup cut its rating of the plane engine maker to 'neutral' from 'buy'.Utilities declined, dragged down by Centrica following a downgrade from UBS to 'sell' from 'neutral'. UBS said increasing political scrutiny was hurting UK utility companies such as Centrica, which are under pressure over the prices they charge customers ahead of next year's general election in Britain.Top performing sectors so far todayFixed Line Telecommunications 4,755.94 +1.78%Oil Equipment, Services & Distribution 23,151.20 +1.01%Oil & Gas Producers 8,036.46 +0.99%Software & Computer Services 1,187.77 +0.95%Financial Services 7,870.06 +0.86%Bottom performing sectors so far todayAerospace and Defence 4,808.80 -1.13%Personal Goods 24,745.94 -0.71%Mobile Telecommunications 5,156.04 -0.37%Electricity 9,262.33 -0.33%Gas, Water & Multiutilities 5,712.15 -0.33%RD