Zelenskiy to extend Ukraine martial law

Russian troops in Mariupol
Russian forces say 959 Ukrainian fighters have surrendered in Mariupol after a steel works siege. -AP

President Volodymyr Zelenskiy plans to extend both martial law and conscription in Ukraine for a further three months as Russia says nearly 700 more Ukrainian fighters have surrendered in Mariupol.

Ukrainian parliamentary support for the measures, listed in proposals published on Wednesday, is regarded as secure and so martial law appears set to continue in the country until August 23, the eve of Ukrainian independence day.

Zelenskiy first imposed martial law on February 24, just hours after Russian tanks first rolled over its borders, and he has since extended it twice by 30 days.

Experts consider the planned length of time martial law is imposed as a good indicator of how long the government expects fighting to last.

More than a day after Ukraine announced it had ordered its garrison in Mariupol to stand down, the ultimate outcome of Europe's bloodiest battle for decades remained unresolved. 

Ukrainian officials halted all public discussion of the fate of fighters who had made their last stand there.

"The state is making utmost efforts to carry out the rescue of our servicemen. Let's wait. Currently, the most important thing is to save the lives of our heroes," military spokesman Oleksandr Motuzaynik told a news conference. 

"Any information to the public could endanger that process."

Russia said 694 more fighters had surrendered overnight, bringing the total number of people who had laid down arms to 959. 

The leader of pro-Russian separatists in control of the area, Denis Pushilin, was quoted by a local news agency DNA as saying the main commanders were still inside the plant.

Ukrainian officials had confirmed the surrender of more than 250 fighters on Tuesday but they did not say how many more were inside or what might become of them.

"Unfortunately, the subject is very sensitive and there is a very fragile set of talks going on today, therefore I cannot say anything more," Mariupol Mayor Vadym Boichenko said. 

He said Zelenskiy, the Red Cross and the United Nations were involved in talks but gave no details.

Negotiations over Mariupol's surrender came as Finland and Sweden formally applied to join NATO, bringing about the very expansion that Russian President Vladimir Putin has long cited as one of his main reasons for launching the "special military operation" in February.

The final surrender would bring a close to a near three-month siege of the port city of more than 400,000 people, where Ukraine says tens of thousands of civilians died under Russian bombardment.

Ukrainian officials have spoken of arranging a prisoner swap for Mariupol defenders. 

Russia says no such deal was made for the fighters, many from a unit set up by Ukrainian ultra-nationalists in 2014 and later incorporated as a regiment in Ukraine's national guard, which it calls Nazi.

Russia says more than 50 wounded fighters have been brought for treatment to a hospital, and others have been taken to a prison, both in towns held by pro-Russian separatists.

Russia's defence ministry posted videos of what it said were Ukrainian fighters receiving hospital treatment after surrendering at Azovstal.

One man shown lying on bed said he had access to food and doctorswhile a second said he had been bandaged and had no complaints about his treatment. 

It was not possible to establish if the men were speaking freely.

The Kremlin says Putin has personally guaranteed the humane treatment of those who surrender. 

Other Russian politicians have called for them to be kept captive and even for their execution.

The Swedish and Finnish ambassadors handed over their NATO membership application letters in a ceremony at the alliance's headquarters in Brussels.

"This is a historic moment which we must seize," NATO Secretary-General Jens Stoltenberg said.

President Joe Biden said the US would work with Finland and Sweden to stay vigilant against any threats while their membership was being considered.

Turkey has said in recent days it will block the Nordic members' accession unless they do more to crack down on Kurdish militants on their territory.

with reporting from DPA