London midday: BT leads market higher

London's top stocks are making good gains helped by BT's full-year numbers and a decent showing from the miners.BT is the strongest riser on news that telecoms giant returned to the black in the last quarter and the full year and reported a 6% rise in the dividend. Pre-tax profit hit £1.01bn in the year to 31 March versus a loss of £244m before.Private equity group 3i is also going well after the group saw a 15% return on its portfolio in the year to March 31 as the companies it invests in participated in the strong rally that followed the economic collapse of the previous year.Supermarket Sainsbury's posted a rise in sales and profits in the year to March 20 and said it was confident of further progress despite expectations of a challenging consumer spending environment. Underlying pre-tax profit of £610m was slightly ahead of expectations and up from £519m a year ago. Sales rose to £21.4bn from £20.4bn and grew 4.3% on a like-for-like basis excluding fuel.Chiefs at ENRC are pleased with the Kazak miner's progress during the first quarter and say the recovery in demand, especially in China, continue to give it confidence for 2010. Riot Tinto and Kazakhmys are also higher in a generally rising mining sector.But financials are keeping the gains to a minimum. Banks Lloyds Banking, Barclays, HSBC Holdings and Standard Chartered are down, while insurers Legal & General Group and Prudential are amongst the top ten fallers.South African insurer Old Mutual continued its momentum from the fourth quarter of 2009 into the current financial year, boosting Long-Term Savings (LTS) by 21% at the start of 2010. Total life assurance sales on an Annual Premium Equivalent (APE) basis for the Long-Term Savings division rose to £397m in the three months ended 31 March, up from £327m a year ago.Travel group Thomas Cook posted narrower losses in the six months to the end of March after continuing to cut capacity to cope with tough economic conditions and said that the impact of the volcano cloud disruption in April would be about £70m. Pre-tax losses totalled £252.2m, less than the £309m shortfall seen in the same period the previous year.The oil spilling out of the damaged rig in the Gulf of Mexico has cost BP $450m so far, the oil giant said on Thursday. The figure includes the cost of spill response, containment, relief well drilling, commitments to the Gulf Coast States, settlements and federal costs.Engineering and project management company AMEC performed in line with expectations in the first four months of the year and said it is seeing some improvement in customer spending. The group said it remains on track to deliver its 8.5 per cent EBITA margin target in 2010. Camping and short break specialist Holidaybreak's half year losses narrowed and it expects full year results to be in line with company forecasts. Headline loss before tax narrowed to £17.7m for the six months ended 31 March from £18.1m the same time a year before. Revenue fell to £150.2m from £153.2m.Oilfield support services group Petrofac has made a good start to 2010 and said it is confident that it will be another year of strong growth.Shares in ground preparation specialist Keller slumped by a fifth as it warned problems in the US would hit its results overall this year.