The government’s deputy national security adviser said China was carrying out “large scale espionage” activities against the UK when asked to provide evidence in the now-collapsed case against two men accused of spying for China.

In a witness statement provided to prosecutors in 2023, Matthew Collins was asked to assess whether Beijing was regarded as a threat to national security at the time two men – Christopher Cash and Christopher Berry – were accused of spying on MPs.

Collins also said in February 2025 that China’s spying threatened “the UK’s economic prosperity and resilience”.

But he made clear the government was “committed to pursuing a positive economic relationship with China”.

The three statements by Collins were given to prosecutors in December 2023, February 2025 and August 2025, and were published by the government on Wednesday night.

The Crown Prosecution Service (CPS) unexpectedly dropped charges against Mr Cash and Mr Berry last month, prompting criticism from ministers and MPs. Both men deny spying for China.

The director of public prosecutions said the case collapsed because evidence could not be obtained from the government referring to China as a national security threat.

Earlier on Wednesday, Sir Keir Starmer said he would publish the deputy national security advisor’s statements after Tory leader Kemi Badenoch accused him of a “cover-up”.

The newly published documents show that in 2023, Collins – who was at the time serving under a Conservative government – described China’s spy agencies as being “highly capable and conduct large scale espionage operations against the UK”.

In a second statement submitted in February 2025, by which time Labour had taken power, he described China as the “biggest state-based threat to the UK’s economic security”.

And in a third statement this August, he said China’s “espionage operations threaten the UK’s economic prosperity and resilience, and the integrity of our democratic institutions”.

Both of the statements from this year stress the government’s position that it wanted to pursue close economic ties with China, with Collins writing: “It is important for me to emphasise, however that the government is committed to pursuing a positive economic relationship with China.

“The government believes that the UK must continue to engage with international partners on trade and investment to grow our economy while ensuring that our security and values are not compromised.”

The government originally said the February 2025 statement, the second of three, was submitted in 2024, but it later clarified on Wednesday night that an error was made when the document was originally signed by Collins.

The documents also contain new details about the activities the two alleged spies were believed to have carried out.

In a statement on Wednesday night Mr Cash said he wanted to reiterate that he was “completely innocent” .

Last month, the Crown Prosecution Service (CPS) unexpectedly dropped charges against the two men, Christopher Cash and Christopher Berry, both of whom deny the allegations.

Mr Cash, a former parliamentary researcher, and Mr Berry were charged under the Official Secrets Act in April 2024, when the Conservatives were in power.

They were accused of gathering and providing information prejudicial to the safety and interests of the state between December 2021 and February 2023.

The director of public prosecutions has said the case collapsed because evidence could not be obtained from the government referring to China as a national security threat.

He said while there was sufficient evidence when charges were originally brought against the two men, a precedent set by another spying case earlier this year meant China would need to have been labelled a “threat to national security” at the time of the alleged offences.

The Conservatives have claimed the government did not provide sufficient evidence because it does not want to damage relations with Beijing.

However, the Labour government has argued that because the alleged offences took place under the Conservatives, the prosecution could only be based on their stance on China at the time.

Speaking at Prime Minister’s Questions earlier, Sir Keir Starmer said: “Under this government, no minister or special adviser played any role in the provision of evidence.”