Pentagon chief Pete Hegseth struck a measured tone towards China at a major defense forum on Saturday, noting "rightful alarm" over Beijing's military build-up but saying Washington sought a "stable equilibrium" in Asia.Hegseth's headline speech at Singapore's Shangri-La Dialogue, which brings together top defense officials and experts from about 45 countries, contrasted with his strongly confrontational remarks on China at last year's gathering.

It came as Donald Trump struggles to resolve the Middle East war -- which has caused oil prices to soar, hurting major Asian economies -- and after the US president met his Chinese counterpart Xi Jinping against the perennial background of tensions over Taiwan.

"When we look across the region today, there is rightful alarm regarding China's historic military build-up and the expansion of its military activities in the region and beyond," Hegseth said.

Washington does not seek "needless confrontation" but rather "a genuinely stable equilibrium (in Asia) that works for Americans as well as our allies", he said.

That means "a favorable but durable balance of power in which no state, including China, can impose its hegemony and hold the security or prosperity of our nation and our allies in question", according to Hegseth.