"I still have no confirmation... The photos show that it really might be [a rifle] FN SCAR… I sent a letter to my counterpart, the Ukrainian Defense Minister [Oleksii Reznikov], on Monday to receive clarification," Dedonder told Belgian newspaper.
The Belgian defense minister also said that Ukraine was responsible for the use of weapons after Brussels had handed them over to Kiev.
"We expect to receive the data, which would confirm or reject the possibility of our arms being used [in the Belgorod Region] and show us the ways they got there," Dedonder was quoted as saying by the newspaper.
The defense minister did not specify the exact dates when she expected to receive Kiev's response on the matter, adding that if Brussels does not get the answer until a meeting of the contact group on Ukraine on June 15, she will personally hold a meeting with Reznikov.
On Wednesday, the Belgian Defense Ministry demanded an explanation from Kiev after Belgian weapons were seen to have been used in Ukraine-orchestrated attacks on Russia's Belgorod Region.
On May 22, Belgorod Region Governor Vyacheslav Gladkov said that a Ukrainian sabotage group had infiltrated the territory of the Grayvoronsky district of the Russian border region; he then announced an anti-terrorist operation.
Last week, the US newspaper reported, citing US officials familiar with intelligence findings, that Ukrainian militants had been armed with Belgian and Czech rifles and at least one AT-3 anti-tank weapon, which was used by US and allied troops. The Ukrainians drove mine-resistant MRAP armored vehicles donated to Ukraine by the US and Poland.