President Xi Jinping yesterday warned that no one can "dictate" China's economic development path as the Communist Party marked 40 years of its historic "reform and opening up" policy amid a stern challenge from the United States.

In a speech at the grandiose Great Hall of the People, Xi vowed to press ahead with economic reforms but made clear that Beijing will not deviate from its one-party system or take orders from any other country.

Without directly referring to the United States, Xi said China "poses no threat" to any country but warned that it would not be pushed around.

"No one is in a position to dictate to the Chinese people what should or should not be done," China's most powerful leader since Mao Zedong told the party faithful.

"We must resolutely reform what should and can be changed, we must resolutely not reform what shouldn't and can't be changed."

While Xi promised more reforms, he did not offer any specifics. The US and Europe have long complained of lingering obstacles to fully entering China's massive market while Chinese companies enjoy the benefits of open Western economies abroad.

"We actively promote the construction of an open world economy, build a community of human destiny, promote the transformation of the global governance system, clearly oppose hegemonism and power politics," Xi said, referencing Chinese geopolitical ambitions.

"China is increasingly approaching the centre of the world stage and becoming a recognised builder of world peace, a contributor to global development, and a defender of the international order."

The commemoration of the reforms enacted under late paramount leader Deng Xiaoping on December 18, 1978, came as China is locked in diplomatic spats and a bruising trade war with the United States. The rivals have agreed to a 90-day truce as they seek to negotiate a solution.

China's reforms pulled hundreds of millions of people out of poverty and turned the country into the world's second biggest economy.

Yesterday's ceremony included the awarding of medals to more than 100 individuals whom the party recognised as key contributors to the country's development.

Deng's reforms broke with Maoist-style collectivisation that left the nation impoverished and backward.

The poverty rate among the rural population dropped to 3.1 percent last year from 97.5 percent 40 years ago. China now boasts the most dollar billionaires in the world with 620.