Russia launched a missile strike on the southern Ukrainian city of Odesa on Wednesday while President Volodymyr Zelensky and Prime Minister Kyriakos Mitsotakis of Greece were visiting.

Neither was hurt, and they continued their visit of Odesa, a strategic port city. It is unclear how close they were to the explosion, and a Ukrainian Army spokeswoman, Natalia Humeniuk, denied that the attack had specifically targeted the state leaders. “This is in no way related to a specific visit,” she said.

Mr. Mitsotakis said at a news conference in Odesa that he and Mr. Zelensky were visiting the city’s port at the time of the assault. “We heard the sound of sirens and explosions that were very close to us,” he said. “We didn’t have time to go to a shelter.”

Dmytro Pletenchuck, a spokesman for the Ukrainian Navy, said that Russia had struck port infrastructure in the city and that five people had been killed. Ms. Humeniuk said Russia had most likely used ballistic missiles.

“You see who we are dealing with,” Mr. Zelensky said. “They don’t care where they strike, whether they are military, civilians, international guests — it doesn’t matter to these people.”

Oleksiy Goncharenko, a Ukrainian lawmaker who was in Odesa at the time of the attack, said it occurred around 10:40 a.m. “I heard explosions, I was very close to the port,” he said in a text message. “It was very loud.”