“Any cargo moving into Ukrainian territory which we would believe is carrying weapons would be fair game,” Mr Lavrov said in an interview with Russia Today yesterday.

Slovakia has said it is ready to send its S-300 system to Ukraine “immediately” provided that it receives a replacement to protect its own airspace.

REPLACEMENT

“We’re willing to do so immediately when we have a proper replacement,” said Slovakia’s minister of Defence Jaroslav Nad at a joint press conference with US Defence Secretary Lloyd Austin last this week.

The S-300 is Slovakia’s only strategic air defence system, he said, adding that handing it over to Ukraine would create a “security gap in NATO”.

Mr Lavrov said Moscow “will not allow” the S-300 system to be given to Ukraine, calling the transfer of the Soviet-era system “illegal”.

He cited intergovernmental agreements and user certificates precluding the transfer of Soviet or Russian-made systems to third countries.

Tomasz Smura, Director of the Research Office at the Casimir Pulaski Foundation, a foreign policy and security think-tank in Warsaw, told The Epoch Times in a phone interview that there often are contractual restrictions regarding the re-export of arms of the type Mr Lavrov mentioned.

But given that Russia’s invasion of Ukraine is a gross violation of international law, he said, Mr Lavrov’s attempt to paint the transfer of the S-300 system as breaking an agreement on arms exports is “simply ridiculous”.

Mr Smura called the Russian’s remarks a scare tactic meant to instil fear in neighbouring countries looking to surge more military aid.

Russia placing its nuclear arsenal on high alert several days after the outbreak of hostilities was a similar move, he said.

SCARE

“Even before the war, Russia had repeatedly tried to scare its neighbours, either with short-range ballistic missiles or by threatening to use nuclear weapons, so this is nothing new.”

Mr Smura added that Russian setbacks in its military campaign in Ukraine are behind Mr Lavrov’s threats to target arms convoys and other attempts to limit military aid.

British intelligence has said Russian forces are mostly bogged down on all fronts amid what it described as a “staunch and well-coordinated” Ukrainian resistance.

“Russian forces have made minimal progress on land, sea, or air in recent days and they continue to suffer heavy losses,” UK intelligence said in a March 17 update.