TOKYO/WASHINGTON, Jan 7 (Reuters) - The United States and Japan on Friday voiced strong concern about China's growing might in unambiguous terms and pledged to work together against attempts to destabilise the region.

The comments from the two allies, in a joint statement that followed a virtual meeting of their foreign and defence ministers, highlight how deepening alarm about China - and growing tension over Taiwan - have put Japan's security role in focus.

The ministers expressed concerns that China's efforts "to undermine the rules-based order" presented "political, economic, military and technological challenges to the region and the world", according to their statement.

"They resolved to work together to deter and, if necessary, respond to destabilising activities in the region," it said.

The ministers also said they had "serious and ongoing concerns" about human rights in China's Xinjiang and Hong Kong regions and stressed the importance of peace and stability in the Taiwan Strait.