By Francesca Gillett & Ruth Comerford for BBC News
A UK Parliamentary researcher and another man have been charged with spying for China after allegedly providing information which could be "useful to an enemy".
Christopher Cash, 29, the researcher, and Christopher Berry, 32, were charged under the Official Secrets Act.
They are accused of giving "articles, notes, documents or information" to a foreign state, the Met Police said.
China has called the allegations "malicious slander".
Counter-terrorism police have described the allegations as "very serious".
Berry, from Witney in Oxfordshire, and Cash, of Whitechapel, London, were arrested last March in connection with the investigation.
It was previously reported that one of the men - Cash - was a Parliamentary researcher involved with the China Research Group, and who is understood to have had access to several Conservative MPs.
The Sunday Times reported the researcher had access to security minister Tom Tugendhat and foreign affairs committee chairwoman Alicia Kearns, among others.
The offences Cash is alleged to have committed are claimed to have happened between 20 January 2022 and 3 February 2023, while those against Berry are alleged to have happened between 28 December 2021 and 3 February 2023.
Cdr Dominic Murphy, head of the Counter Terrorism Command, said it had been an "extremely complex investigation".
"We've worked closely with the Crown Prosecution Service as our investigation has progressed and this has led to the two men being charged today," he said.
"We're aware there has been a degree of public and media interest in this case, but we would ask others to refrain from any further comment or speculation, so that the criminal justice process can now run its course."
The Met said officers previously arrested a man in his 30s at an address in Oxfordshire and a man in his 20s at an address in Edinburgh on 13 March 2023.
Both men were subsequently released on police bail while the investigation continued and a case file was passed to the CPS for consideration in late 2023, police said.
The charge states that "for a purpose prejudicial to the safety or interests of the state, obtained, collected, recorded, published, or communicated to any other person articles, notes, documents or information, which were calculated to be, might be, or were intended to be, directly or indirectly, useful to an enemy".
The two men have been bailed to appear at Westminster Magistrates' Court on Friday 26 April.
Nick Price, head of the CPS's Special Crime and Counter Terrorism Division, said in a statement: "Criminal proceedings against the defendants are active. No-one should report, comment or share information online which could in any way prejudice their right to a fair trial."
A spokesperson for the Chinese Embassy said it had already "made relevant response on September 10 2023".
The spokesperson said: "I would like to reaffirm that the claim that China is suspected of 'stealing British intelligence' is completely fabricated and nothing but malicious slander.
"We firmly oppose it and urge the UK side to stop anti-China political manipulation and stop putting on such self-staged political farce."
Kearns said she would "not be commenting further" on the matter.
"As this matter is now sub judice it is essential that neither I, nor anyone else, say anything that might prejudice a criminal trial relating to a matter of national security," she posted on X.
The term sub judice refers to a case that is currently the subject of ongoing legal proceedings.
Commons Speaker Sir Lindsay Hoyle told MPs that one of those charged was a Parliamentary pass holder and that the case should not be referred to in the chamber to avoid prejudicing "a criminal trial relating to a matter of national security".
- BBC News