May, Macron Agree to Jointly Address 'Aggressive Russian Behaviour'

"They discussed the wide pattern of aggressive Russian behaviour and agreed that it would be important to continue to act in concert with allies to address it… They agreed that the French and British governments should coordinate closely as the investigation developed and following Russia’s response," the UK Prime Minister’s Office spokesman said.

The French president condemned the suspected attack on Skripal and offered his solidarity with the United Kingdom, the statement added.

On Monday, May said that Russia was "highly likely" responsible for suspected poisoning of Skripal, who reportedly also served as an agent for the UK secret intelligence service MI6. May said that the substance, used in the poisoning of Skripal, was identified as a military-grade nerve agent of the so-called Novichok group developed in Russia. Russian Foreign Ministry's spokeswoman Maria Zakharova called May's remarks a "circus show."

Skripal and his daughter Yulia were found unconscious last week on a bench at a shopping center in Salisbury. Both of them remain in critical condition and are being treated for suspected exposure to a chemical.