REpresentative image (File photo) NEW DELHI: China on Monday imposed export controls on 10 US companies involved in defence and rare earths mining, while also banning government procurement agencies from purchasing products made by dozens of American firms, escalating tensions between the world's two largest economies.The measures were announced weeks after the United States expanded its blacklist of companies it says support China's military, a move that prompted Beijing to warn of retaliatory action.China's commerce ministry said the new export controls were aimed at protecting national interests and were a direct response to Washington's latest restrictions.China's new export controls come…