The Trump administration has warned China that the US will target Chinese banks unless Beijing takes much stronger measures to impose economic pain on North Korea by reducing trade and financial transactions with Pyongyang.

Marshall Billingslea, a top Treasury official, told Congress on Tuesday that the US had not seen sufficient evidence that China was willing to curb North Korean revenue flows and “expunge North Korean illicit actors” from its banking system. He said the Trump administration would continue to work with China to maximise pressure on North Korea, but stressed that the US “will not hesitate to act unilaterally”.

His remarks followed the UN Security Council’s vote on Monday to impose another round of sanctions on Pyongyang. China and Russia backed the effort after the US agreed to dilute a proposal to ban all exports of refined petroleum exports to North Korea.