The British records show that the Tibetan government's acceptance of the new border in 1914 was conditional on China accepting the Simla Convention. Since the British were not able to get an acceptance from China, Tibetans considered the McMahon line invalid. Tibetan officials continued to administer Tawang and refused to concede territory during negotiations in 1938. The governor of Assam asserted that Tawang was "undoubtedly British" but noted that it was "controlled by Tibet, and none of its inhabitants have any idea that they are not Tibetan." During World War II, with India's east threatened by Japanese troops and with the threat of Chinese expansionism, British troops secured Tawang for extra defence.