Russian President Vladimir Putin ordered unexpected military drills in the Black Sea on Thursday.
"Today at 4:00 a.m. the president of the Russian Federation and supreme military commander (Putin) gave the order to the defense minister to begin major military exercises in the Black Sea region," said Putin's spokesman Dmitry Peskov.
"We are talking about major exercises, intended as a check," he added.
Officials say the surprise drills are meant to test Russia's combat readiness, but as Reuters points out, "the order also seemed aimed at sending a signal to the West that Russia is an important presence in the region."
"It is flexing muscles and may have more to do with what is happening in the Mediterranean, around Syria, than in the Black Sea," Fyodor Lukyanov, editor of the journal Russia in Global affairs, told Reuters.
Russia does not have to give prior notice of military drills unless the number of military personnel involved exceeds 7,000.
"According to international practice, exercises involving up to 7,000 people do not require us to inform our partners in advance," Peskov said.
Peskov also said 36 navel ships would be involved in the exercises, though he did not specify how many aircraft.