India is set to give final approval to a $2.6 billion deal for military helicopters from U.S. defence firm Lockheed Martin ahead of a visit by U.S. President Donald Trump this month, defence and industry sources said. Prime Minister Narendra Modi's government is trying to pull out all the stops for Trump's trip in a bid to reaffirm strategic ties between the two countries, which have been buffeted by sharp differences over trade, to counter China. India's defence purchases from the United States have reached $17 billion since 2007 as it has pivoted away from traditional ...