Force Z was spotted during the afternoon of 9 December by the , and floatplanes from several Japanese cruisers spotted the British ships later that afternoon and shadowed them until dark. Admiral Sir Tom Phillips decided to cancel the operation as the Japanese were now alerted. Force Z turned back during the evening, after having tried to deceive the Japanese that they were heading to Singora. At 00:50 on 10 December, Admiral Philips received a signal of enemy landings at Kuantan and correspondingly altered course so that he would arrive shortly after dawn.