Britain's Prime Minister Theresa May views the area where former Russian double agent Sergei Skripal and his daughter were found critically ill, in Salisbury. File picture: Toby Melville/Pool Photo via AP

Brussels - British Prime Minister Theresa May said she would tell other European Union leaders on Thursday that Russia posed a threat to the whole bloc, not only to Britain, following an attack using a military-grade nerve agent in England.

"Russia staged a brazen and reckless attack against the United Kingdom," May told reporters on arriving at an EU summit. "It's clear that the Russian threat does not respect borders and indeed the incident in (the town of) Salisbury was a pattern of Russian aggression against Europe and its near neighbours." 

The inside of The Mill pub in Salisbury where traces of the nerve agent used to poison Russian double agent Sergei Skripal was found. File picture: Andrew Matthews/PA via AP

People leave the Russian Embassy in London. Nearly two dozen Russian diplomats were ordered to leave Britain as part of a standoff over a nerve agent attack on British soil. Picture: Frank Augstein/AP

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