Twenty-three Russian diplomats expelled from the UK over the poisoning of a former spy on British soil have begun their journey to Moscow, Russia state news agency TASS reported.
Around 80 people, including the diplomats' families, were due to fly out of London on Tuesday to the Russian capital. A Reuters video showed a small crowd gathered outside the Russian embassy, hugging and waving goodbye to others boarding vehicles with diplomatic plates.
Russia and the UK have been embroiled in a bitter diplomatic row since Russian former double agent Sergey Skripal, 66, and his daughter, 33-year-old Yulia Skripal, were poisoned in the English cathedral city of Salisbury on March 4.
The pair remain critically ill in the hospital, while a British police officer also fell ill from exposure to the substance, which British officials believe was the military-grade nerve agent Novichok.
UK Prime Minister Theresa May accused Russia of orchestrating the attack.
Putin calls row 'delirium'
Russian officials have repeatedly denied carrying out the poisoning, and President Vladimir Putin described the accusations as "delirium" on Sunday, in comments after winning another six years as president.
UK Foreign Secretary Boris Johnson said that the Russian denials were growing grow "increasingly absurd."
"One time they say that they never made Novichok, another time they say did make Novichok but all the stocks have been destroyed," he said Monday at a NATO meeting in Brussels.
"I think what people can see is that this is a classic Russian strategy of trying to conceal the needle of truth in a haystack of lies and obfuscation.
Russia's foreign ministry has retaliated by ordering 23 British diplomats leave the country as well.
The ministry also declared it was closing the British consulate in St. Petersburg as well as the British Council, a cultural institute with artistic, language and educational programs.
Russian Senator Igor Morozov, a veteran of the Russian Service of External Intelligence, claimed the British Council was being used as a cover for UK intelligence agencies, state-run RIA Novosti news agency reported. The British Council said it was "profoundly disappointed" by Moscow's decision to order its closure.
London's Metropolitan Police is also investigating the death of Russian businessman Nikolai Glushkov, who was found dead last week in his London home. They are now treating the case as murder.
A post-mortem exam on the Russian exile, who had links to compatriots who died in mysterious circumstances in the UK, "gave the cause of death as compression to the neck," a police statement said.
There's no evidence at this stage that his death and the attack on the Skripals are linked, it said.