Beijing says representatives of 90 countries are taking part in this week's Xiangshan Forum, a gathering of military and diplomatic officials billed as its answer to the annual Shangri-La Dialogue in Singapore.

Russian Defence Minister Sergei Shoigu is also attending.

China is holding the forum without a sitting defence chief, having abruptly announced the sacking of minister Li Shangfu last week without explanation.

Zhang Youxia, one of China's most senior military officials, did not name the nations "creating turmoil" in his address, but Beijing has kept up a steady drumbeat of criticism of the United States for its positions on Russia's invasion of Ukraine and the Israel-Hamas conflict.

"As we look across the world today, hotspot issues are arising one after another. The pain of war, chaos and turmoil, and loss of life are constantly playing out," Zhang said.

"However, some countries, for fear that the world may stabilise, deliberately create turmoil, interfere in regional issues, interfere in other countries' internal affairs, and instigate color revolutions," he said.

"For the sake of their own selfish interests, they bury nails everywhere. They create many artificial geopolitical conflicts, then preach impartiality while actually favouring one side, making regional situations complex and intractable," he added.

"Behind the scenes, they hand out knives and think nothing of provoking people into wars, ensuring that they're the ones who benefit from the chaos."

Speaking after Zhang, Russia's Shoigu also warned that Washington was seeking to provoke instability in Asia.

"Having provoked an acute crisis in Europe, the West is trying to expand the crisis potential in the Asia Pacific," he told delegates.

"Direct involvement of countries with nuclear arsenals multiplies the strategic risks," he said.

"The West's line towards escalation with Russia poses a risk of direct conflict between nuclear powers, which will result in catastrophic consequences," Shoigu added.

China has refused to condemn Russia's invasion of Ukraine and has deepened economic, diplomatic and military cooperation with Moscow since the start of the war.