Russia expelled 59 diplomats from 23 countries on Friday and said it reserved the right to take action against four other nations in a worsening standoff with the West over the poisoning of a former Russian spy and his daughter in Britain.

Russia said it was responding to what it called the baseless demands for scores of its own diplomats to leave a slew of mostly Western countries that have joined London and Washington in censuring Moscow over the poisoning of Sergei Skripal and his daughter Yulia.

A day earlier, Moscow ordered the expulsion of 60 U.S. diplomats and the closing of the U.S. consulate in St Petersburg, Russia's second city, in retaliation for the biggest ejection of diplomats since the Cold War.