The European Union has imposed sanctions on Russian military intelligence chiefs over the nerve agent attack on a former Russian double agent in Britain last year.
EU foreign ministers meeting Monday in Brussels slapped travel bans and asset freezes on four Russians, including the head and deputy head of Russia's military intelligence, for the attack on Sergei Skripal and his daughter, Yulia.
Moscow dismissed the sanctions as groundless. Kremlin spokesman Dmitry Peskov said "we have still not heard any evidence" against the accused.
A Russian foreign ministry statement said, "We reserve the right to take retaliatory measures over this unfriendly step."
Russia has denied charges it was behind the nerve agent attack on the Skripals. The two Russian men accused of carrying out the attack have said they were innocent tourists.
"Today's new sanctions deliver on our vow to take tough action against the reckless and irresponsible activities of the Russian military intelligence organization, the GRU, which put innocent British citizens in serious danger in Salisbury last year," said British Foreign Secretary Jeremy Hun.
Syrian research center
EU foreign ministers Monday also imposed sanctions on a Syrian research center and its staff for its alleged use of chemical weapons.
The ministers said in a statement that the new sanctions contribute "to the EU's efforts to counter the proliferation and use of chemical weapons, which poses a serious threat to international security.''