Jim O’Neill, the Treasury minister and former Goldman Sachs chief economist, could quit the government over Theresa May’s new approach to China exposed by her handling of plans for a new Hinkley Point nuclear plant.

Lord O’Neill was a star signing brought into the Treasury by George Osborne to build relations with China and oversee new infrastructure. He coined the phrase “Brics” in 2001 to describe the world’s leading emerging economies, Brazil, Russia, India and China.

In a sign of the remaining tensions in Mrs May’s new ministerial team and concerns in Beijing that it may no longer be welcome to invest in British nuclear power plants, Lord O’Neill has told friends he will leave the government in September unless Mrs May can explain why she wants him to stay on.