WASHINGTON, September 15. /TASS/. The US administration believes that the expulsion of two US diplomats from Russia was groundless and will not be left unanswered, US Department of State Spokesperson Matthew Miller has told reporters.

In his words, the Russian side "informed Ambassador Lynne Tracy of the decision to declare two US diplomats persona non grata."

"This unprovoked expulsion of our diplomatic personnel is wholly without merit, as is the case against a former Russian contractor of our embassy who was arrested for the supposedly nefarious task of performing such activities as providing our embassy with media clips," the spokesman said.

"Yet again, Russia has chosen confrontation and escalation over constructive diplomatic engagement. It continues to harass employees of our embassy, just as it continues to intimidate its own citizens. We regret that Russia has taken this path, and you can certainly expect that we will respond appropriately to their actions," he added.

When asked when retaliatory measures should be expected, Miller replied: "I don’t want to preview that, but we have acted expeditiously in the past in response to such actions by the Russian Federation."

He added that those embassy staffers have not yet left the country.

Answering to a question of whether Russian Ambassador to the US Anatoly Antonov will be summoned to the US Department of State in connection with the matter, the spokesperson said: "I don’t want to speak to exactly the steps that we are taking to respond, but you can certainly expect that we will do so."

"I’m not going to say when we’re going to take those steps. We will make those clear to the Russian Government, and we will make them clear to you at the appropriate time," Miller said.

The Russian Foreign Ministry said earlier that it summoned US Ambassador to Russia Lynne Tracy and issued her a diplomatic note stating that the actions of the embassy’s first and second secretaries were inconsistent with diplomatic status. They were declared personae non gratae and have to leave the country within seven days, it said.