In 2023, Beijing's forces "experienced a new wave of corruption-related investigations and removals of senior leaders which may have disrupted its progress toward stated 2027 modernization goals," the congressionally mandated annual report on Chinese military and security developments said.

At least 15 high-ranking military officers and defense industry executives were removed from their posts between July and December 2023, according to the report.

"Several leaders investigated or removed for corruption oversaw equipment development projects related to modernizing the PRC's ground-based nuclear and conventional missiles," it said, using an abbreviation for the People's Republic of China.

The 2027 goals that may be impacted include "boosting the speed of modernization in military theories, organizations, personnel, and weapons and equipment," according to the report.

A senior US defense official noted that "frequent turnover and replacement of high-level personnel certainly can be disruptive," while efforts to uncover corruption can slow down projects and also spiral from one official to others who are connected.

Chinese leader Xi Jinping has overseen a wide-ranging campaign against official corruption since coming to power just over a decade ago, with critics saying it also serves as a way to purge political rivals.

Recent efforts have focused on the People's Liberation Army, with top official Miao Hua joining last month a host of high-ranking figures removed from their positions in just over a year.

- 'Cold War mentality' -

But the Pentagon also said on Wednesday that China's military -- which it has been working to modernize for several decades -- has made recent advances.

That included in the realm of operational nuclear warheads, which increased from more than 500 last year to more than 600 in 2024.

Beijing's "expanding nuclear force will enable it to target more US cities, military facilities, and leadership sites than ever before in a potential nuclear conflict," it said.

Its air force is also making gains and "is rapidly approaching technology typical of US standards."

And China has "the world's leading hypersonic missile arsenal and has dramatically advanced its development of conventional and nuclear-armed hypersonic missile technologies during the past 20 years," according to the report.

Beijing hit back on Thursday, saying that the report was "full of bias."

"It is just an excuse for maintaining (the United States') own military hegemony," foreign ministry spokesman Lin Jian said when asked about the report at a regular news briefing.

"We urge the US side to abandon its Cold War mentality... and stop sending, year after year, these irresponsible reports and to work toward maintaining stability between the United States and China," he added.

The United States has identified China as its most consequential challenge, but insists that conflict is not inevitable and aims to deter an attack on Taiwan by Beijing's forces through American military deployments in the Pacific and a network of allies in the region.

China claims Taiwan as part of its territory and has said it will never renounce using force to seize it one day, while the United States has a longstanding arrangement to provide Taipei with the means to defend itself.