The U.S. is the only meaningful counterweight to China's growing global influence, but given the "blunt reality" of America's challenging fiscal position other countries will have to "step up to the plate" and contribute, U.K. Secretary of Defense Philip Hammond said.
"Only the U.S. can respond to the challenge that is represented by China's growing power," Hammond said in an interview with CNBC at the Shangri-La Dialogue in Singapore at the weekend. "The U.S. can lead, and the U.S. must lead, but it can't do everything on its own."
His comments follow increased tensions in the South China Sea over the placement of a Chinese oil rig in contested waters, which reportedly led the Chinese coast guard to ram Vietnamese boats, while violent anti-China demonstrations in Vietnam have left six people dead.
Read MoreWhat is Beijing's end-game in South China Sea?
While the U.S. has no position on territorial claims in Asia, U.S. Secretary of State Chuck Hagel warned China in a fiery address to the Shangri-La Dialogue that the U.S. will not "look the other way" if the international order is challenged.
Hammond reiterated that geopolitical conflicts in Asia must be resolved in accordance with the rule of law and the norms of international behavior, and encouraged regional militaries to work together more closely.
"By building areas of military cooperation, areas where we can collaborate, where we do have alignment, we can defuse tensions, get a better understanding of each other's practices and doctrines, and make it less likely that there will be a miscalculation in a period of tension," he said.
Read MoreUS warns China against aggression in South China Seas
Relations between Tokyo and Beijing have also soured in recent months following a dispute in the East China Sea over islands known as Senkaku in Japan and Diaoyu in China.
Hammond welcomed Japanese Prime Minister Shinzo Abe's recent offer to play a bigger part in Asian regional security. He voiced support for Abe's attempt to modernize Japan's constitution to allow for the expansion of Japanese self-defense forces.