Russia’s military is preparing an “appropriate” response to Ukraine’s alleged use of Baltic territory to launch drone attacks, Kremlin spokesman Dmitry Peskov said Wednesday.

“This problem exists, and our relevant services, primarily the military in this case, are closely monitoring the situation and formulating our country’s necessary response,” Peskov told the pro-Kremlin tabloid Izvestia, though he did not specify the scope of the measures.

The warning comes a day after Russia’s Foreign Intelligence Service (SVR) on Tuesday threatened Latvia, stating its NATO membership would not “protect” it from Moscow’s retaliation for Riga allegedly allowing Ukraine to fire drones from inside its borders.

Latvia’s foreign minister accused the SVR of running a disinformation campaign amid an internal political crisis triggered by Ukrainian drones straying into Latvian airspace and crashing.

U.S. Deputy Representative to the UN Tammy Bruce said that “there is no place for threats” against Latvia, assuring member states that Washington “keeps all of its NATO commitments.”