"We expected something like this, frankly," the US Indo-Pacific Command deputy commander told an audience in Canberra.

"Just because we expect that behaviour does not mean that we should not condemn it, and we need to condemn it publicly," he said.

"It is concerning."

Sklenka said other nations besides the United States should speak out against the drills.

"It's one thing when the United States condemns the Chinese, but there's a far more powerful effect, I believe, when it comes from nations within this region," the lieutenant general told reporters.

"I also believe in my heart of hearts that conflict between our two nations is not inevitable, and it's not a foregone conclusion."

Sklenka said he believed the "target" of China's exercises was its own domestic population, not the international community.