Iran's foreign minister said Monday that Tehran would not remain "indifferent" if it becomes evident Russia is using Iranian-made drones in Ukraine.
His remarks came as Ukrainian President Volodymyr Zelensky said Russia ordered around 2,000 drones from Iran, the same kind that Kyiv says Moscow has been using in its recent attacks against Ukraine.
"During the war in Ukraine... we are against arming both Russia and Ukraine," Iran's Foreign Minister Hossein Amir-Abdollahian said in video remarks published by local media.
"We have not supplied Russia with any weapons or drones for use in the war against Ukraine," he continued, reiterating previous denials whilst acknowledging that the two countries have defence cooperation.
Iran's top diplomat reaffirmed his country's willingness to hold direct talks with Ukraine on the matter, and said that he conveyed this to European foreign policy chief Josep Borrell in the past days.
"I stressed to Mr Borrell that if... it becomes clear to us that Russia has used Iranian drones in the war against Ukraine, we will definitely not be indifferent about this issue."
Kyiv and its Western allies have repeatedly accused Moscow of using Iranian-made drones in attacks on Ukraine in recent weeks.
Iran has previously rejected allegations that it has supplied Russia with weapons "to be used" in Ukraine, while the Kremlin said Western countries aim to "pressure" Tehran.
Earlier on Monday, Iran's foreign ministry spokesman Nasser Kanani rejected US allegations that Iranian military personnel are on the ground in Russian-occupied Crimea to help Moscow carry out drone attacks in Ukraine.
"We strongly reject this news," Kanani said in a press conference.
The claim by Washington "aims to deviate public opinion from the destructive role they have in the Ukraine war by standing on one side of the conflict and heavily exporting weapons and equipment to Ukraine," he added.
On Thursday, White House national security spokesman John Kirby said Iranian forces are "on the ground in Crimea" to assist Russia in its operations, adding that the personnel are trainers and tech support workers.
Kirby said "Tehran is now directly engaged on the ground, and through the provision of weapons that are impacting civilians and civilian infrastructure in Ukraine".
The United States, alongside Britain and the European Union, have already imposed sanctions on Iran over the issue of drones.
Last month, Kyiv decided to significantly reduce its diplomatic relations with Tehran over alleged arms deliveries to Moscow.