The Footsie is set for a negative start to today's session following a flat finish yesterday after US President Barack Obama denounced Russia's actions in Crimea and ahead of data out both Stateside and in the UK. City sources predict the top tier index will open around 30 points lower than yesterday's close of 6,605.30, dragged by last night's steep sell-off on Wall Street.Speaking in Brussels, Obama warned that the US would impose "more sanctions" on Russia if it continues to escalate the crisis in Ukraine following last week's annexation of Crimea. "If Russia stays on its current course the costs for the Russian economy will continue to grow," he said."Currently the sanctions are seen as weak, but are likely to be significantly ramped up in the next few days if Russia do not comply," said Chief Market Analyst James Hughes from Alpari.Less than impressive core durable goods orders also dragged the index lower. The data showed that orders for durable goods jumped by 2.2% in February to a seasonally adjusted $229.4bn, according to data from the Commerce Department, surprising analysts who had expected a rise of just 0.8%.However, the positive surprise was mainly as a result of large increases in the volatile transportation sector. Excluding this, goods orders rose by a more modest 0.2%, lower than the 0.3% gain expected by the market. As such, core capital goods orders (ex-defence and aircraft) - seen as an important measure of business investment - actually dropped by 1.3% over the month; analysts had expected a 0.5% rise.Turning to today's agenda, a report is due to be released on UK retail sales and is expected to show a 2.9% year-on-year increase in February following a 4.8% rise a month earlier.Over in the States, US gross domestic product (GDP) will be in focus and is tipped to register an annualised 2.7% growth in the fourth quarter, up from 2.4% the previous quarter. US initial jobless claims and pending home sales data will be also be released.In this morning's company news, after long negotiations that became public in November, engineering group Babcock announced it has finally agreed to acquire helicopter services provider Avincis for £920m. The FTSE 100 company, which will also assume Avincis' net debt of £705m, will fund the purchase with a £1.1bn rights issue.London Stock Exchange revealed strong trading at its secondary and primary markets divisions during the last 11 months of its financial year and said momentum has continued across the group. The exchange said total equity capital raised during the 11 months to date increased 91% to £28.3bn, with 162 new issues compared to 107 in 2013.Thomas Cook said travel bookings for the winter season are 93% sold despite market disruptions. Winter bookings were adversely affected by continued social unrest in Egypt but the company said it was "successfully mitigated through the more integrated management processes and improved customer service that we introduced last year".Oil explorer Tullow has given a mixed drilling update on rigs currently operating in its 50%-owned blocks 10BB and 13T onshore Kenya. "The early exploration, appraisal and testing activities onshore Kenya are giving us significant technical and operational insights for further optimising and accelerating the development of the basin," said Exploration Director Angus McCoss.NR