Izmail, Ukraine - Kyiv on Monday controversially claimed Iranian-made Russian drones fell and detonated on Romanian territory during an overnight strike on the Ukrainian port of Izmail, something that Ukraine's NATO member neighbor strongly denied.

"According to the State Border Guard Service of Ukraine, Russian 'Shaheds' fell and detonated on Romanian territory overnight," Ukrainian foreign ministry spokesman Oleg Nikolenko said on social media.

He said the incident took place during a massive Russian attack near Izmail, located on the Danube river, across from Romania.

The spokesman shared an image of what appeared to be a bright cloud of smoke near a body of water.

Joke of the Day Joke of the Day for September 15, 2024: The best jokes to get your funny on

A spokesman for the State Border Guard Service told AFP that Nikolenko's account was "reliable" and that two detonations had been observed.

"We recorded two detonations on the territory of Romania near the Izmail port during the Russian attack overnight," Andriy Demchenko said.

Following its withdrawal from an agreement in July allowing the export of Ukrainian grain through the Black Sea, Moscow has pounded ports in Ukraine's south including Izmail.

Romania meanwhile categorically denied that Russian drones fell on its soil during the strike.

"At no time did the means of attack used by the Russian Federation pose a direct military threat to Romania's national territory or territorial waters," its defense ministry said.

While most fighting during Russia's invasion has taken place within Ukraine's borders, Kyiv has occasionally claimed the conflict has spilled over into European countries, claims that its NATO allies have largely dismissed.

Joke of the Day Joke of the Day for September 14, 2024: The best jokes to get your funny on for Caturday

In March 2022 a Soviet-made Tupolev drone crashed into the Croatian capital Zagreb causing no injuries, and in November a missile landed on a Polish village near the Ukrainian border, killing two people.

Ukraine suggested Russia was behind both incidents but in both case its Western allies dismissed this, suggesting instead that they were of Ukrainian origin and had fallen there accidentally.