Russia has reportedly deployed ten warships with three more joining en route to the Mediterranean Sea off the coast of Syria, making for the single largest Russian flotilla to reach Syrian shores since the Kremlin began providing direct military support to embattled President Bashar al Assad, and is among the largest demonstrations of Russian naval power since the end of the Cold War. The group, led by the guided missile cruiser Marshal Ustinov, is said to be heavily equipped with Russia’s own version of the Tomahawk cruise missile, known as the Kalibr. The Kalibr has seen successful use in Syria before, being launched from a number of naval platforms including submarines.

“The Russian Navy has dispatched substantial naval forces to the Mediterranean, including several ships equipped with modern cruise missiles,” NATO spokesperson Oana Lungescu told the press on Tuesday. “We will not speculate on the intention of the Russian fleet, but it is important that all actors in the region exercise restraint and refrain from worsening an already disastrous humanitarian situation in Syria. NATO is not present in Syria, but we support the efforts of the United Nations to achieve a lasting political resolution to the conflict.”

This most troubling aspect of this recent show of force is how soon it came after a new round of Russian claims regarding secret American plans for another missile strike against Assad’s Syrian regime. The United States military has conducted two such strikes in the past, both under the direction of President Donald Trump, and both as a direct result of reports of chemical weapons being used against civilians by Assad’s Russian backed forces. Russia has repeatedly claimed that the United States has been supporting ISIS throughout Syria and even that they staged the chemical weapon attacks themselves in order to justify taking military action against Assad, presumably with the intention of eventually removing him from power. However, the limited extent of both missile strikes (the more recent of which saw participation from the U.K. and French forces as well) would seem to suggest that the United States was more intent on sending a message than they were on anything else.

It’s most likely that this flotilla will help to support Assad’s forces as they push into the Syrian city of Idlib, a refuge for civilians and rebel forces alike, some of whom receive military support from the United States and its allies. The region has proven difficult to operate in for Syrian and Russian forces alike, with rebels even successfully shooting down a Russian Su-25 Frogfoot fighter jet in February of this year.