
The government’s deputy national security adviser warned in 2023 that 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.
A second witness statement written by Matthew Collins in February 2025 as evidence for the case of two men accused of spying on MPs, Christopher Cash and Christopher Berry, said China’s spying threatened “the UK’s economic prosperity and resilience”.
A third witness statement published in August restated the UK’s view of the challenge posed by China.
But the second two statements made clear the government was “committed to pursuing a positive economic relationship with China”.
All three statements were published by Downing Street on Wednesday night as the government continued to face questions after the Crown Prosecution Service (CPS) unexpectedly dropped charges against Mr Cash and Mr Berry last month, prompting criticism from ministers and MPs.
The first of the three statements by Collins was given to prosecutors in December 2023, when he was serving under a Conservative government.
The second and third statements were submitted this year after Labour had taken power.
Previously, 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 adviser’s statements after Tory leader Kemi Badenoch accused him of a “cover-up”.
The documents show that in December 2023, Collins concluded: “The Chinese Intelligence Services are highly capable and conduct large scale espionage operations against the UK and other international partners to advance the Chinese state’s interest and harm the interests and security of the UK.”
In February 2025, he said: “China is an authoritarian state, with different values to the UK. This presents challenges for both the UK and our allies. China and the UK both benefit from bilateral trade and investment, but China also present 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”.
He pointed to a number of actions which UK authorities believe Beijing was behind, including a cyber-attack on the UK electoral commission between 2021 and 2023.
In his 2025 statements, Collins made clear the government sought a good economic relationship with China, 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, had been made when the document was originally signed by Collins.
BBC News understands that Collins assumed he had given enough evidence for the prosecution to continue when he submitted his third witness statement in August 2025.
A government source pointed to comments made by him where he described “the increasing Chinese espionage threat posed to the UK” as an example of why he believed he had said enough to satisfy the CPS’s threshold for prosecution.
It is also understood that the CPS contacted Collins after his first witness statement to ask for further clarification on the threat posed by China, but that they were not explicitly clear what the official would need to say in subsequent statements, in order to meet the CPS’s threshold.
New details of alleged spying
In his first statement, Collins writes in detail about the allegations made about Mr Cash and Mr Berry, which he said was based on information provided to him by counter terrorism police.
Both men have denied the allegations against them.
Collins said in this 2023 statement “it had been assessed that the Chinese state recruited Mr Berry as an agent and successfully directed him to utilise Mr Cash” who had access to the Commons China Research Group (CRG) and other MPs.
Mr Cash worked as a parliamentary researcher and was involved with the CRG, which was set up by a group of Conservative MPs looking into how the UK should respond to the rise of China.
In his statement, Collins said that in July 2022, Mr Berry met with a senior Chinese Communist Party leader and that he understands Mr Cash was made aware of the meeting by Mr Berry.
Collins said Mr Cash responded to Mr Berry with multiple messages, including one reading: “You’re in spy territory now”.
Collins also said information gathered was passed to an individual named “Alex” who was believed to be an agent of the Chinese state.
This included information about the prospect of Tom Tugendhat MP being made a minister and the likelihood of Jeremy Hunt pulling out of the Conservative leadership race.
In a new statement released on Wednesday evening, Mr Cash said he was “completely innocent”.
He said: “I have been placed in an impossible position. I have not had the daylight of a public trial to show my innocence, and I should not have to take part in a trial by media.
“The statements that have been made public are completely devoid of the context that would have been given at trial.”

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.”
The publication of the documents followed pressure from the Conservatives and the Liberal Democrats, who had called for them to be released.
On Tuesday, senior government figures had suggested that the CPS had told them publishing the witness statements would be “inappropriate”.
But the CPS later made clear it would not stand in the way if ministers chose to put the government’s evidence in the public domain.