The Shangri-La Dialogue, Asia's top international defence forum, kicks off in the city-state on Friday.

The meeting has historically offered rare opportunities for senior officials to hold face-to-face talks, and will be attended by US Defense Secretary Pete Hegseth this year.

But his Chinese counterpart, Dong Jun, will not be in attendance, Beijing's defence ministry said at a Thursday press conference.

Instead, the People's Liberation Army National Defense University has sent a delegation to take part, ministry spokesman Zhang Xiaogang said.

The delegation "will have in-depth exchanges with different parties to build more consensus", he said.

Zhang did not say why Dong was not attending or whether the Chinese team would meet with US counterparts.

Asked who was leading Beijing's delegation, he said he had "nothing more to add".

Dong's absence comes after reports last year said he had been placed under investigation for corruption, something Chinese authorities have not confirmed.

If true, Dong would be the third consecutive Chinese defence minister to come under a graft probe, following the removal of his predecessors Li Shangfu and Wei Fenghe.