Russian President Vladimir Putin has said he does not see any point in meeting Volodymyr Zelensky after the Ukrainian leader requested face-to-face talks over ending the war between the two nations.

Zelensky sent an open letter on Thursday calling for direct negotiations with Putin, writing that it was "wrong to simply wait" for the war, which began with Russia's full-scale invasion of Ukraine in 2022, to become the focus of US attention once more.

The Ukrainian president also requested a ceasefire, while striking a defiant, at-times mocking tone.

Putin called the note "rude" and refused the request for a meeting, reiterating his position that peace talks should precede any ceasefire.

"I don't see any point for now," he said when asked whether he would take up Zelensky's offer while speaking at Russia's annual economic forum in St Petersburg on Friday.

"Was it a way to create the conditions for a face-to-face meeting or a way not to set up a face-to-face meeting? I think it was the second."

After hearing Putin's response Zelensky said Russia "was choosing war again" .

"He just doesn't want to end the war. I think that many in the world were disappointed by this answer," he wrote on Telegram.

During his remarks addressing Zelensky's letter, Putin restated his position that a ceasefire would only allow Ukraine to regroup, while concessions Moscow is seeking from Kyiv remain unmet.

"The only point is for the Ukrainian side to halt the advance of our armed forces. But we need agreements - not for six months, not for three months, but for the long term," he said.

"Let the experts get to work and come up with some solutions. After that, we can meet."

Putin said he would only end the war when Russia's goals had been met.

"Military actions will end some day, we assume. Without a doubt, they will end once we have achieved the goals we have set for ourselves."

Russia's longstanding position is that Ukraine should withdraw from the Donetsk, Luhansk, Kherson and Zaporizhzhia regions, as well as abandon efforts to join Nato.

But Kyiv has refused to give up any territory, arguing that any concessions to Moscow would embolden it to invade again in the future, noting its full-scale invasion came eight years after it annexed the Crimean peninsula.

Zelensky had stated in his letter that "after 26 years in power, age is beginning to take its toll" on Putin, while drawing attention to a recent Ukrainian strikes on Russian territory - including one on St Petersburg on Thursday he described as "paying a visit".

Putin said the letter contained "some rather rude remarks".

The content of Zelensky's letter had raised hopes of peace in some quarters, including the White House.

US President Donald Trump said "it would be great" if the two leaders did meet.

Ukraine said on Friday that it had struck five ships with illegal cargo in the Sea of Azov and in coastal waters of territories occupied by Russia.

Robert Brovdi, Ukraine's drone commander, said they had been involved in "stealing" Ukrainian grain, and transferring fuel and military supplies.

Azerbaijan's foreign ministry said five people had been killed in attacks on two of the ships in the sea of Azov. It did not indicate who it thought had carried out the attack and said the boats did not belong to Azerbaijan.

One drone operated by Ukraine exploded in the Romanian Black Sea port of Constanta. Ukrainian operators said it was knocked off course by Russian electronic interference.

At least 13 people have been killed and 70 others injured in a series of Russian attacks on Ukraine in the past day, officials have said.

Four died after a dairy factory was hit outside Kyiv, while a drone strike on a petrol station in Kherson killed a 35-year-old woman.