US Defense Secretary Chuck Hagel, on the eve of a trip to China, called on Beijing to use its "great power" responsibly and said he would urge its leaders to respect neighbors increasingly anxious over its posture in territorial disputes.
"Great powers have great responsibilities. And China is a great power," Hagel said, adding he wanted to talk with China about its use of military power, and encourage transparency.
Hagel was speaking during a visit to ally Japan, where there is growing concern over China's military buildup and its increasingly assertive posture in a territorial dispute with Tokyo over islands in the East China Sea.
"Something else that ... I will be talking with the Chinese about is respect for their neighbors. Coercion, intimidation is a very deadly thing that leads only to conflict," he said. "All nations, all people deserve respect."
In unusually strong language almost certainly meant to reassure Japan, a treaty ally that the United States has pledged to defend, Hagel pointed to the example of Russia's annexation of Crimea as the kind of action that would not be tolerated.
"You cannot go around the world and redefine boundaries and violate territorial integrity and the sovereignty of nations by force, coercion or intimidation, whether it's in small islands in the Pacific, or in large nations in Europe," he said.
Japan has drawn parallels between Russia's actions in Crimea and what it sees as China's challenge to the status quo in East China Sea.
Hagel, who leaves for a three day visit to China on Monday, hosted talks last week with Southeast Asian defense ministers where he also warned of growing US concern about territorial disputes in the South China Sea.