Early on Monday morning, barge pilots and workers on the Romanian side of the river opposite the Ukrainian Danube port of Reni stared in disbelief at the skies, filming a swarm of approaching drones on their smartphones.
As the tiny dots in the sky came closer and their high-pitched buzz grew louder, the men's astonishment quickly turned to panic. "They're going to let them explode here," shouted one. "They're going to hit the port!"
A few hundred meters away, the flash of a first explosion was followed by the sound of a massive detonation. "Let's get out of here, lads," shouted another man. "The war has just reached Romania's border!"
Dawn had just broken over the Danube Delta when Russia sent 15 Iranian Shahed-136 drones to attack the port of Reni. Some of the drones were shot down by Ukrainian air defenses; others exploded in the port, destroying warehouses and silos used to store Ukrainian grain. Seven people were injured, and one Romanian cargo ship was damaged in the attack.
The port of Izmail further downstream was also attacked, but no damage was done.
A stone's throw from NATO's border
This is the closest Russia's war on Ukraine has come to NATO's external border. Reni is situated close to the border between Ukraine, Romania and the Republic of Moldova, about 120 kilometers (75 miles) west of where the Danube flows into the Black Sea.
The destroyed grain facilities in the port are just 200 meters (218 yards) from the center of the river, which marks Ukraine's border with NATO-member Romania, and 400 meters from the Romanian bank of the river.
The Moldovan Danube port of Giurgiulesti is just five kilometers upstream, and the Romanian city of Galati, which has a population of 220,000, is just 10 kilometers away as the crow flies. It is sheer luck that the Shahed drones, which are not known for their accuracy, didn't land on the NATO side of the border.
Russia steps up strikes on Ukrainian ports
The attack on Reni is an escalation of Russia's campaign of air strikes on Ukrainian port cities, which began a week ago in Odesa and Mykolaiv and has so far mainly targeted the infrastructure needed to export Ukrainian grain.
Since the start of the war, Russian rockets have passed through Romanian airspace, Russian rocket debris has landed in the Republic of Moldova, and a Russian rocket has hit a Polish forest. But this is the first time, Russia has intentionally hit a civilian target so close to NATO's external border in a region that has no significant military infrastructure.
An attempt to paralyze Ukraine's grain exports
"[Russian President] Vladimir Putin wants to paralyze Ukraine's grain exports by any means possible and, at the same time, take revenge for the fact that certain sanctions against Russia — such as those in the banking sector — have not been lifted," said Bucharest-based political scientist Armand Gosu, who teaches Russian and Soviet history and diplomacy at the University of Bucharest.
Ukraine is heavily reliant on income from the sale of grain and oilseed and has three routes for exporting both commodities. The first and most important route, even after Russia's invasion of Ukraine on February 24, 2022, is via the Black Sea ports of Odesa and Mykolaiv. This route remained open thanks to an internationally mediated deal with Russia last year.
Since the start of the war, Ukraine has also been using a second route — over land via Romania, Hungary, Slovakia and Poland — to get its grain to the world market. The third export route centers on the Ukrainian Danube ports of Reni and Izmail and the part of the Black Sea that belongs to Romania's territorial waters. Ukraine is keen to develop this route considerably.
Ukraine's main Danube ports
The port in the city of Reni (population: 18,000) in Ukraine's southwestern corner is not easy to reach by land, but is the more easily navigable of the two ports. Even larger cargo ships can travel from Reni to the Black Sea via Romania's Sulina Canal, the most developed arm of the river in the Danube Delta.
The port of Izmail (population 70,000) is on the northern Chilia arm of the Danube Delta. Although it is easier to reach by land than Reni, its port cannot be used by many large cargo ships.
A project to deepen certain parts of the Danube in the region — such as the Novostambulske/Bystroye Canal — is progressing very slowly and has been a bone of contention between Romania and Ukraine for many years.
Putin wants to highlight 'NATO's indecisiveness'
Compared with the Black Sea route via Odesa and Mykolaiv, only a tiny proportion of Ukraine's grain has been exported via the Danube ports. When seen from this perspective, the risk for Russia of attacking Reni — given its location on the border with NATO-member Romania — would seem to be much greater than the benefit.
According to Armand Gosu, the motivation behind the attack was not just to paralyze Ukraine's grain exports. "Putin wants to show that he doesn't care how close his attacks are to NATO territory," Gosu told DW. "What's more, Putin's goal is to highlight NATO's indecisiveness."
Romanians shocked by proximity of attack
The Romanian public reacted with shock and concern to the attack on Reni, not only because the war has come so close to their country, but also because there are close historical, linguistic and cultural ties between the peoples of the Danube Delta. More than half of the inhabitants of Reni, for example, are ethnic Romanians.
In sharp contrast to the public's response, official reactions in Romania were very restrained. Romanian President Klaus Iohannis briefly tweeted his strong condemnation of Russia's attacks on his country's border, while the Romanian Defense Ministry issued a statement saying there was "no direct military threat to the national territory."
The NATO-Ukraine Council met on Wednesday to discuss the security situation in the Black Sea region. It "strongly condemned Russia's decision to withdraw from the Black Sea grain deal" and "Moscow's cynical drone attack on the Ukrainian grain storage facility in the Danube port city of Reni" and confirmed in firm, but non-aggressive terms that it remains "ready to defend every inch of Allied territory from any aggression."
Armand Gosu explained these restrained responses to DW by saying that NATO wants "to avoid an escalation at any cost," adding that "the elites in the West have grown tired of the war and are more afraid of the collapse of Russia than a Ukrainian defeat."
Adapted from the German by Aingeal Flanagan.