Belgium will ask Ukraine for clarification on reports that Belgian-made rifles were used by pro-Ukrainian forces to fight Russian troops on Russia's western border.

 This was announced on Monday by Belgian Prime Minister Alexander De Croo, Reuters reports.

 On Saturday, The Washington Post, citing intelligence, reported that the fighters of the Russian Volunteer Corps and the Legion of Freedom of Russia, which fight on the side of Ukraine and invaded the Belgorod region at the end of May, used at least four tactical vehicles previously transferred to Ukraine western states.

 "Our Ministry of Defense and its intelligence agencies have launched an investigation and are asking for information to determine exactly what happened," de Croo said on Belgian radio station Radio 1.

 "European weapons are supplied to Ukraine under the condition that they will be used on Ukrainian territory for the purpose of defending that territory. And we conduct strict controls to make sure that this is the case," he said.

 De Croo declined to comment on the possible consequences if the reports are confirmed.

 "We should not rush ahead. But we are analyzing the situation and will take it very seriously," said the Prime Minister.

 On Sunday, with reference to sources, it was reported that the Ministers of Defense and Foreign Affairs of Belgium, Lyudivin Dedonder and Aja Lyabib, will contact the Ukrainian authorities as soon as possible to get an explanation of the situation.