Russia expels UK diplomat over spying in a fresh diplomatic spat

Russia has expelled a British diplomat it accused of spying, telling London it would not tolerate "undeclared" intelligence officers operating on its territory, accusations that have ignited a fresh diplomatic feud with London.

"Moscow will not tolerate the activities of undeclared British intelligence staff on its territory," the foreign ministry said in a statement on Tuesday, saying it was expelling him for lying on his accreditation and visa application.

Britain has rejected the claims one of its embassy employees was a spy, the latest in a string of espionage allegations that come with relations between the two countries running at an all-time low.

The spat also comes a week after Ukraine was given permission to start firing UK-supplied long-range missiles at Russia - drawing scorn and threats of direct military retaliation from President Vladimir Putin - and after Russia arrested a British man captured fighting for Ukraine.

The Foreign Ministry in Moscow summoned British ambassador Nigel Casey after the FSB security services said they had uncovered a British spy.

The FSB said the British diplomat, identified as the embassy's second secretary, appeared to have carried out "intelligence and subversive work, threatening the security of the Russian Federation."

'Baseless accusations'

The UK government rejected the allegations and pledged a response.

"This is not the first time that Russia has made malicious and baseless accusations against our staff. We will respond in due course," said a foreign office spokesperson.

London and Moscow have expelled several of each other's diplomats on spying allegations in recent years.

The FSB said the man expelled on Tuesday was a replacement for one of six British officials that Russia had kicked out earlier this year, also on espionage charges.

Relations between the two capitals have been repeatedly strained by intelligence scandals and accusations throughout Putin's quarter-century in power.

The UK has accused Moscow of being behind the 2006 assassination of former Russian agent and Kremlin critic Alexander Litvinenko in a London poisoning attack.

And in 2018, Britain and its allies expelled dozens of Russian embassy officials they said were spies over the attempted poisoning of former double agent, Sergei Skripal, with Soviet-era nerve agent Novichok.

Skripal, who lived in exile in London, survived the attack but a British civilian died after touching a contaminated perfume bottle, triggering uproar in London.