NATO accused Russia on Friday of reckless behaviour and pledged to "defend every inch of allied territory" after Romania said a Russian drone had crashed into an apartment block in the military alliance member state during an attack on neighbouring Ukraine.
"Who in Romania says that this is a Russian drone?" Putin asked reporters at a news conference in Astana, Kazakhstan.
He said he had only just heard of the incident as he had been in talks all day.
"No one can say what the origin of this or that drone is until an examination has been carried out," he said.
Putin said that Ukrainian drones had previously been spotted in Finland, Poland and in the Baltic countries.
"The first reaction was exactly the same as it is now in Romania: the Russians are coming," Putin said.
"Then, after a short time, it turned out that it had nothing to do with Russian drones."
During the night, a drone crashed into a residential building in the Romanian city of Galati, near the border with Ukraine.
Two people were injured.
In response, Bucharest summoned the Russian ambassador and closed the consulate general in Constanta.
A number of European Union and NATO countries have condemned the incident as a Russian escalation.
Putin on Friday also pushed back against remarks by European Commission president Ursula von der Leyen, who accused Russia of crossing another line with the incident, saying that she had not examined the drone debris herself.
Putin suggested that Romania share information about what happened and potentially drone fragments so that Russia could conduct its own investigation.
Ukrainian President Volodymyr Zelenskiy said on Friday that Russia was preparing a major new attack on his country.
"We have intelligence information about Russia preparing a new large-scale strike," Zelenskiy said in his nightly video address.
"Our services are responding promptly and are prepared. The Air Force and other defenders of the sky will work 24/7, as they always do."
Russian authorities said on Monday they intended to launch "systematic strikes" on targets in Kyiv and warned foreigners and diplomats to leave.
They said the action was in response to a drone strike last week on a dormitory in Ukraine's Russian-held Luhansk region which killed 21 people.
Ukraine denied carrying out the attack.
with DPA
