The head of the FBI and the leader of Britain’s domestic intelligence agency have raised fresh alarms about the Chinese government, warning business leaders Beijing is determined to steal their technology for competitive gain.

FBI Director Christopher Wray reaffirmed longstanding concerns in denouncing economic espionage and hacking operations by China, as well as the Chinese government’s efforts to stifle dissent abroad.

His speech was notable because it took place at MI5’s London headquarters and alongside the agency’s director general, Ken McCallum, in a show of Western solidarity.

“We consistently see that it’s the Chinese government that poses the biggest long-term threat to our economic and national security, and by ‘our’, I mean both of our nations, along with our allies in Europe and elsewhere,” Mr Wray said.

Mr McCallum said the Chinese government and its “covert pressure across the globe” amounts to “the most game-changing challenge we face”.

“This might feel abstract. But it’s real and it’s pressing,” he said.

A spokesman for the Chinese embassy in Washington, Liu Pengyu, rejected the allegations, saying in an emailed statement to The Associated Press that China “firmly opposes and combats all forms of cyber attacks” and calling the accusations groundless.

“We will never encourage, support or condone cyber attacks,” the statement said.

In a nod to current tensions between China and Taiwan, Wray also said during his speech that any forcible takeover of Taipei by Beijing would “would represent one of the most horrific business disruptions the world has ever seen”.

Last week, the US government’s director of national intelligence, Avril Haines, said at an event in Washington there were no indications Chinese President Xi Jinping was poised to take Taiwan by military force.

But she did say President Xi appeared to be “pursuing the potential” for such an action as part of a broader Chinese government goal of reunification of Taiwan.

Wray said he would leave to others the question of whether an invasion of Taiwan was more or less likely after Russia’s invasion of neighbouring Ukraine.

“I don’t have any reason to think their interest in Taiwan has abated in any fashion,” he said, adding he hoped China had learned what happens “when you overplay your hand”, as he said the Russians have done in Ukraine.

The FBI director said there are signs the Chinese, perhaps drawing lessons from Russia’s experience since the invasion, have looked for ways to “insulate their economy” against potential sanctions.

“In our world, we call that behaviour a clue,” Mr Wray said.

President Joe Biden said in May the US would respond militarily if China invaded Taiwan, offering one of the most forceful White House statements in support of Taiwan in decades.

The White House later tried to soften the impact of the statement, saying President Biden was not outlining a change in US policy towards Taiwan, a self-governing island China views as a breakaway province that should be reunified with the mainland.

Embassy spokesman Liu said in his statement the Taiwan issue was “purely China’s internal affair” and that when it comes to questions of China’s territory and sovereignty, the country has “no room for compromise or concession”.

“We will strive for the prospect of peaceful reunification with utmost sincerity and efforts,” he said, noting that China will “reserve the option of taking all necessary measures in response to the interference of foreign forces”.

– AAP