The United States and its European allies are expelling dozens of Russian diplomats in a coordinated response to the poisoning of a former Russian spy in the UK.

US President Donald Trump has ordered 60 Russian diplomats to leave the country.

Germany, France, Ukraine, Canada and various European countries have also expelled envoys.

Russia called the moves a "provocative gesture" and vowed to retaliate.

Russia denies any role in the attack on Sergei Skripal and his daughter, Yulia, in Salisbury, southern England. The pair remain in a critical but stable condition in hospital.

EU leaders agreed last week it was highly likely Russia was behind the nerve-agent poisoning.

British Prime Minister Theresa May said the show of solidarity gave a strong message.

"We welcome today's actions by our allies, which clearly demonstrate that we all stand shoulder to shoulder in sending the strongest signal to Russia that it cannot continue to flout international law," a statement from Mrs May's office said.

Various countries announced they were making the same move in solidarity on Monday. These are:

• US: 60 diplomats
• Ukraine: 13
• Poland: 4
• France: 4
• Germany: 4
• Canada: 4
• Czech Republic: 3
• Lithuania: 3
• Netherlands: 2
• Italy: 2
• Denmark: 2
• Estonia: 1
• Latvia: 1
• Croatia: 1
• Finland: 1
• Romania: 1

Read more on BBC.