President Donald Trump ordered the expulsion of 60 Russian diplomats from the United States in response to the use of chemical weapons against a known enemy of the Russian government in the United Kingdom.

The United States will close a consulate in Seattle, sending 48 diplomatic staff back to Russia. Washington will also retire 12 diplomats from the United Nations.

“To the Russian government we say, when you attack our friends you’ll face serious consequences,” a U.S. government official said in a briefing with reporters Monday.

The official described the “malicious attempt” by Russia to undermine the sovereignty of countries around the world, arguing that the attack against former Russian spy Sergei Skripal and his daughter was only the latest example.

The diplomats have seven days to return to Russia.

The administration described the Salisbury attack as a“reckless attempt” by the government that endangered civilians in the UK. An official said the United States was working with allies to send a strong message to Russia that “actions have consequences.”

The official accused the Russian diplomats of using the cover of their roles in the United States to cloak their intelligence activities.

“This reduces Russia’s ability to spy on American citizens, conduct covert operations on our soil and threaten our national security,” he said.

A senior White House official declined to say whether Trump had spoken to Russian President Vladimir Putin about the chemical attacks but reiterated that the two leaders spoke on the phone last Tuesday.