The United States says it reserves the right to take further action againt Russia, following Moscow's decision to shutdown its consulate in St Petersburg and expel 60 diplomats in the ongoing row over the Skripal poisonings.
"We don't see this as a diplomatic tit-for-tat," said State Department spokesperson Heather Nauert. "Russia is responsible for that horrific attack on the british citizen and his daughter. Once again, they have broken the chemical weapons convention. It was a banned substance that was used, novichok, we take this very seriously."
Doctors says Yulia Skripal is showing rapid improvement in hospital and there are reports she's recovered consciousness.
Her father remains in a critical condition following their poisoning in the English city of Salisbury at the beginning of the month.