The Russian government is ratcheting up warnings – on Twitter – to the U.S. government not to interfere with its military operations in Syria, even suggesting American aircraft could be targeted by its “air defense systems.”

In a provocative tweet Wednesday, the Russian embassy in Washington posted a side-by side photo of White House Press Secretary Josh Earnest and the Russian S-300 missile system.

With the military apparatus pointed toward the image of Earnest, a caption says Russia wants the system because they “never really know what kind of assistance terrorists might get.” The tweet says Russia will take “every defensive measure necessary” to protect their personnel in Syria.

The tweet comes after the U.S. and Russia suspended direct talks over Syria operations -- and amid heightened tensions between the two countries over the bloody civil war in which Vladimir Putin’s forces are backing Bashar Assad while the U.S. tries to focus on taking out ISIS.

Asked what message the Russians might have been trying to send, Earnest tried to laugh off the social media salvo.

“I have no idea what message they were trying to send. If they’d like better pictures, though, I'm happy to send some,” Earnest joked at Wednesday’s briefing.  

The photo coincides with other recent threats by Russian officials that Moscow would respond militarily to any perceived interference as the country boosts its military presence in Syria.

Fox News first reported that the SA-23 Gladiator anti-missile system, which is part of the S-300VM system, has been deployed to Syria – marking the first time it’s been deployed outside Russia.

Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov claimed the system was sent to defend against attacks by terrorist groups, including ISIS and Nusra, which is an Al Qaeda-linked group based in Syria.

And the Russian embassy in the U.K. used its Twitter feed to poke fun at Western officials who view the deployment as concerning.

The “S-300 in Syria shouldn't frighten anyone. It's a defensive weapon. It cannot be more transparent,” said the tweet.

However, Defense Department spokesman Peter Cook noted in his Tuesday briefing that neither ISIS nor Nusra have air forces that would warrant using a defensive missile system.

Russia has been conducting air strikes in support of Assad since September 2015, but the diplomatic situation has deteriorated since Russian fighters reportedly bombed a United Nations convoy bringing aid to Aleppo on Sept. 19.

Moscow denied any responsibility and the Russian embassy in Canada this week blamed the attack on a “well-prepared hoax.”

Since the disintegration of talks, Russian embassies around the world have been posting tweets to mock the U.S. role in Syria and applaud its own military prowess.

On Wednesday, their embassy in Canada posted photos purportedly from Aleppo that showed no damage or destruction.

On Thursday, Konashenkov reportedly warned that there would be no time to alert counterparts if they detect a threat. 

“Russian S-300, S-400 air defense systems deployed in Syria's Hmeymim and Tartus have combat ranges that may surprise any unidentified airborne targets. Operators of Russian air defense systems won't have time to identify the origin of airstrikes, and the response will be immediate. Any illusions about 'invisible' jets will inevitably be crushed by disappointing reality," he reportedly said

The Washington Post recently reported the Obama administration is weighing potential strikes against the Assad regime – the White House has neither confirmed nor denied the report. 

Following Konashenkov's comments, Cook said Thursday that the U.S. will "continue to conduct our operations as we have for months now over Syria" and "continue to take every possible step we need to to ensure the safety of our air crews [and] coalition air crews in Syria." 

Fox News' Lucas Tomlinson contributed to this report.