WASHINGTON, March 30. /TASS/. Russia's retaliatory response to expel US diplomats "marks a further deterioration in the United States-Russia relationship," the White House said in a statement on Thursday.

"The expulsion of undeclared Russian intelligence officers by the United States and more than two dozen partner nations and NATO allies earlier this week was an appropriate response to the Russian attack on the soil of the United Kingdom," the White House said.

"Russia’s response was not unanticipated and the United States will deal with it," the statement added.

On March 26, the United States announced its decision to expel 60 Russian diplomats and close the Russian Consulate General in Seattle. Twenty-four European countries, Canada and Australia also decided to expel a total of 63 Russian diplomats. NATO reduced the number of staff members of the Russian mission from 30 to 20. The EU recalled its ambassador for consultations, and Bulgaria, Luxembourg, Malta, Portugal and Slovakia followed suit. The UK earlier expelled 23 Russian diplomats and Moscow announced a tit-for-tat move.

This concerted action came amid the poisoning of former Russian military intelligence officer Sergei Skripal and his daughter, Yulia, in Salisbury, the UK, on March 4. London immediately accused Russia of being involved, but failed to provide any evidence. Moscow has rejected allegations and vowed to respond to the unfriendly steps against it.

Russia has declared 58 employees of the US Embassy in Moscow and two staff members of the Consulate General in Yekaterinburg personae non gratae, they will have to leave the country by April 5, Russia’s Foreign Ministry said on Thursday after the US Ambassador to Russia Jon Huntsman was summoned there. Besides, Moscow has revoked its consent to the opening and operations of the US Consulate General in St. Petersburg.