China has sent a delegation of officials and companies on a buying trip to the US, reviving its practice of cheque book diplomacy just as political pressure mounts in the US over Beijing’s currency policy, writes Geoff Dyer in Beijing.

Led by the commerce vice-minister, a group of 50 executives and officials arrived in the US on Wednesday to begin placing orders for US-made goods on the same day that a congressional hearing began to investigate the alleged undervaluation of the Chinese renminbi.

Timothy Geithner, the US Treasury secretary, told the committee in written testimony that China’s efforts to strengthen its currency since abandoning a dollar peg in June had been “too slow and…too limited”. The Obama administration that day opened two fresh cases against China, for breaching global trade rules, at the World Trade Organisation.