Ukrainian President Volodymyr Zelenskyy has returned home, from a visit to Turkey, with five commanders of Ukraine’s former garrison in Mariupol, a move Russia said violated the terms of a prisoner exchange deal engineered last year.

Kremlin spokesman Dmitry Peskov said on Saturday that Ankara had promised under the exchange agreement to keep the men in Turkey and complained that Moscow had not been informed of the move.

The five commanders, lionised as heroes in Ukraine, led last year’s defence of the southern port of Mariupol, the biggest city Russia has captured in its invasion. Thousands of civilians were killed inside Mariupol when Russian forces laid the city to waste during a three-month siege.

Zelenskyy on Saturday posted a one-minute video showing himself and other officials shaking hands and hugging the smiling commanders before they boarded a Czech aeroplane together.

“We are returning home from Turkey and bringing our heroes home,” said Zelenskyy, who met Turkish President Recep Tayyip Erdogan for talks in Istanbul on Friday.

“Ukrainian soldiers Denys Prokopenko, Svyatoslav Palamar, Serhiy Volynsky, Oleh Khomenko, Denys Shleha. They will finally be with their relatives,” he said on the Telegram messaging app.

Kyiv had finally ordered the Ukrainian defenders, who held out for weeks in tunnels and bunkers under a steel plant, to surrender in May last year. Russia freed some of them in September last year in a prisoner swap brokered by Ankara under terms that required the commanders to remain in Turkey until the end of the war.

Zelenskyy gave no explanation for why the commanders were being allowed to return home now and there was no immediate comment from Turkey.

Many Ukrainians hailed the news on social media.

“Finally! The best news ever. Congratulations to our brothers!” Major Maksym Zhorin, who is fighting now in eastern Ukraine, said on Telegram.

‘Direct violation’

The Kremlin, however, accused Ukraine and Turkey of violating agreements by releasing the commanders.

“The return of the leaders of the Azovites from Turkey to Ukraine is nothing more than a direct violation of the terms of the existing agreements. Moreover, in this case, the terms were violated by both the Ukrainian side and the Turkish side,” said Peskov, the Kremlin spokesman.

“No one informed us about this. According to the agreements, these ringleaders were to remain on the territory of Turkey until the end of the conflict,” he said.

Peskov added that the release was a result of heavy pressure from Turkey’s NATO allies ahead of next week’s summit of the military alliance at which Ukraine hopes to receive a positive sign about its future membership.

In a ceremony alongside the men in the western city of Lviv, Zelenskyy thanked Erdogan for helping secure the soldiers’ release and pledged to bring home all remaining prisoners.

He said that before the outbreak of war, “many people in the world still did not understand what we are, what you are, what to expect from us and what our heroes are. Now everyone understands”.

Denys Prokopenko, one of the five commanders, told the gathering that his men “will have our word to say” in the counter-offensive launched by Ukrainian forces in the past month.

“The most important thing is that Ukraine has seized the strategic initiative and is advancing,” he said.

Analysts said the return of the soldiers could strain Turkey’s relations with Russia. Ankara has so far managed to maintain a delicate balancing act, even helping broker a deal with Russia last year that allowed the safe export of grain and fertiliser from Ukrainian ports.

“Turkey’s a member of NATO, which has been backing Zelenskyy and Ukraine in the war. But at the same time, Erdogan has maintained good relations personally with President [Vladimir] Putin of Russia,” Bulent Ali Riza, the founding director of the Turkey Project at the Center for Strategic and International Studies (CSIS), told Al Jazeera.

“Erdogan has not applied sanctions, unlike the other members of the Western alliance and he’s been able to do this successfully. Until now, he’s been able to broker the grain deal because he has connections with both sides. And yet, with these most recent moves that he has made – hosting Zelenskyy and then releasing the Azov fighters – is obviously going to be interpreted by Russia as heavily tilted to the other side,” Bulent said,

500 days of war

The repatriation of the commanders came as Ukraine marked the 500th day of Russia’s full-scale invasion. In honour of the day, Zelenskyy released a video of him visiting Snake Island, a Black Sea outcrop that Russian forces seized on the first day of the invasion last year and later abandoned.

Speaking from the island, Zelenskyy honoured the Ukrainian soldiers who fought for the territory and all other defenders of the country, saying that reclaiming control of the island is “great proof that Ukraine will regain every bit of its territory”.

“I want to thank – from here, from this place of victory – each of our soldiers for these 500 days,” the Ukrainian leader said. “Thank you to everyone who fights for Ukraine!”

United States Secretary of State Antony Blinken marked the 500 days by describing Russia as “the sole obstacle to a just and lasting peace” and promising to back Kyiv “for as long as it takes”.

France’s foreign ministry said the time frame “must bring Russia to the realisation that it is in an impasse and immediately stop its illegal war of aggression”.

The latest US pledge of support included plans to supply widely-banned cluster munitions. Ukrainian Defence Minister Oleksii Reznikov promised the munitions would not be used in Russia.

The General Staff of Ukraine’s Armed Forces said Ukrainian troops on Saturday “continued offensive operations” in two sectors in the southeast.

Officials said that a Russian rocket strike on the town of Lyman killed eight civilians and wounded 13 others early on Saturday. Pavlo Kyrylenko, the governor of Ukraine’s eastern Donetsk region, posted images showing some of the dead, including a body lying under a bicycle and body fragments on the pavement next to a damaged vehicle, saying that “the Russian terrorists are continuing to strike civilians in Donetsk”.

Lyman is a few kilometres from the front line, where Russian troops have recently intensified fighting in the forests of Kreminna.

The United Kingdom’s Ministry of Defence, meanwhile, said in its latest intelligence update that the eastern town of Bakhmut captured by the Russians in May has seen some of the most intense fighting along the front during the last week.

It said that Ukrainian forces have made steady gains in both the north and south of Bakhmut. “Russian defenders are highly likely struggling with poor morale, a mix of disparate units and a limited ability to find and strike Ukrainian artillery,” the ministry added.

ncG1vNJzZmivp6x7orjJmrGenaKWe6S7zGilnq%2BjZH9xfpJobmhwX6q4s63Ip5ysZaqauaa60qSwsmWimsG2vs2sZJqyn6t6pLvMppinnJWnwG6%2BxKWcmquVmXq1u4ytrKujla4%3D