Russia’s Federal Security Service on Friday accused six British diplomats of spying and said a decision has been made to withdraw their accreditation.

Russian state TV quoted an official from the security service known as the FSB as saying that they will be expelled.

The FSB claimed that it received documents indicating that they were sent to Russia by a division of the U.K. Foreign Office “whose main task is to inflict a strategic defeat on our country,” and that they were involved in “intelligence-gathering and subversive activities.”

The move comes two days after the United States and Britain pledged nearly $1.5 billion in additional aid to Ukraine, and as Ukrainian officials renewed their pleas to use Western-provided missiles against targets deeper inside Russia.