UK's MI5 warns lawmakers of spying threat from China, Russia and Iran

The UK's domestic spy service MI5 has warned lawmakers that spies from China, Russia and Iran are targeting them in a bid to undermine British democracy.

Security guidance issued by the agency late on Monday said spies may seek to gather information from MPs and their staff through blackmail, phishing attacks and building long-term relationships with them.

Politicians should also be wary of attempts to exploit them online and while travelling abroad, and financial donations as a way to gain access and influence, MI5 warned.

The UK is a target of long-term strategic foreign interference and espionage from elements of the Russian, Chinese and Iranian states, which all use different tactics, it said.

"When foreign states steal vital UK information or manipulate our democratic processes they don't just damage our security in the short-term, they erode the foundations of our sovereignty and ability to protect our citizens' interests," MI5 Director General Ken McCallum said in a statement.

MI5 referenced previous cases of political interference in British politics, including the case of Christine Lee.

In January 2022, MI5 issued a security alert to lawmakers warning that the London-based lawyer was "involved in political interference activities" in the UK on behalf of China's Communist Party.

The alert said MI5 had found that Lee had "facilitated financial donations to serving and aspiring parliamentarians on behalf of foreign nationals based in Hong Kong and China".

Although not charged with any criminal offence, Lee later sued MI5, arguing that its alert was politically motivated and violated her human rights. She lost the case last year.

MI5's security guidance comes a month after the collapse of a case against two British men accused of spying on UK lawmakers for Beijing.

The UK's top prosecutor said the charges were dropped because the government had refused to designate China as an "enemy" and a threat to national security.

Speaking in parliament on Monday, UK Security Minister Dan Jarvis said that the government had made "every effort ... to provide evidence in support of this case".