Chinese intelligence is mounting “large-scale” espionage operations against the UK and its allies as it attempts to steal technology and distort political decision-making, the chief of MI6 has warned.

In his first public speech since taking up the post last year, Richard Moore said the threat posed by a newly-assertive China was now “the single greatest priority” for his agency.

Speaking at the International Institute for Strategic Studies in London he warned a “miscalculation” by an over-confident regime in Beijing over an issue like Taiwan could pose a “serious challenge” to global peace.

In a wide-ranging address, Mr Moore said Russia continued to represent an “acute threat” to the UK while the Taliban victory in Afghanistan had given a “morale boost” to extremists around the globe.

On China, Mr Moore said the activities of their intelligence agencies included targeting individuals working in government or industries they were interested in as well as seeking to monitor and exert “undue influence” on the Chinese diaspora.

“The tectonic plates are shifting as China’s power, and its willingness to assert it, grows,” he said.

“The Chinese intelligence services are highly capable and continue to conduct large-scale espionage operations against the UK and our allies.

“We are concerned by the Chinese government’s attempt to distort public discourse and political decision making across the globe.”

Mr Moore said Beijing’s growing military strength and its desire to achieve its long-standing claim to Taiwan issue, by force if necessary, posed “a serious challenge to global stability and peace”.

“Beijing believes its own propaganda about Western frailties and underestimates Washington’s resolve. The risk of Chinese miscalculation through over-confidence is real,” he said.

He said the “surveillance state” technologies which China had developed to suppress its own people, such as the minority Uighur population, were being made available to other authoritarian regimes.

“Worryingly, these technologies of control and surveillance are increasingly being exported to other governments by China: expanding the web of authoritarian control around the planet,” he said.

“Adapting to a world affected by the rise of China is the single greatest priority for MI6. We need to be able to operate undetected as a secret intelligence agency within the surveillance web worldwide.”

On Russia, Mr Moore said that it was essential for Western countries to stand up to the “full spectrum” of threats from Moscow – from state-sanctioned attacks, such as the Salisbury poisoning” to the use political political proxies to undermine stability in the Balkans.

“No country, in Europe or beyond, should be seduced into thinking that unbalanced concessions to Russia bring better behaviour,” he said

“Moscow should be in no doubt of our allies’ support for the sovereignty and territorial integrity of Ukraine, within its internationally-recognised borders including Crimea.”

On Afghanistan, Mr Moore said the priority was to prevent the country being used again as a base for major international terrorist attacks by groups like al Qaida now it was back in control of the Taliban.

“As an intelligence community we will now do this ‘outside in’: working from the outside to identify and disrupt any threats from a resurgent al Qaida,” he said.

“This is an extremely difficult task, and will rely extensively on regional partnerships as well as coordination with our allies.”

At the same time, he said MI6 was “engaging” with the Taliban and testing their willingness to cooperate and to honour their promises not to allow al Qaida to rebuild an external operations capability.