Ukrainian president Volodymyr Zelenskiy has warned Russian withdrawals from the north and centre of the country are just a military tactic to build up forces for new powerful attacks in the south-east.
A new round of talks between the countries was scheduled for Friday, five weeks into a conflict that has left thousands dead and driven 4 million Ukrainians from the country.
“We know their intentions,” Mr Zelenskiy said in his nightly video address to the nation.
“We know that they are moving away from those areas where we hit them in order to focus on other, very important ones where it may be difficult for us.”
“There will be battles ahead,” he added.
Mr Zelenskiy asked the Australian parliament on Thursday to send armoured vehicles to Ukraine, to which the southern country’s leader said the following day he would oblige.
Australian prime minister Scott Morrison said the country will send Bushmaster vehicles on Boeing C-17 Globemaster transport planes, though he did not specify how many would be sent or when.
Meanwhile in Mariupol, Russian forces blocked a convoy of 45 buses attempting to evacuate people after the Russian military agreed to a limited cease-fire in the area. Only 631 people were able to get out of the city in private cars, according to the Ukrainian government.
Russian forces also seized 14 tons of food and medical supplies in a dozen buses that were trying to make it to Mariupol, Ukraine's deputy prime minister Iryna Vereshchuk said.
The city has been the scene of some of the worst suffering of the war.
Tens of thousands have managed to get out in the past few weeks by way of humanitarian corridors, reducing the population from a pre-war 430,000 to an estimated 100,000 by last week, but other relief efforts have been thwarted by continued Russian attacks.
The International Atomic Energy Agency said it had been informed by Ukraine that the Russian forces at the site of the world’s worst nuclear disaster had transferred control of it in writing to the Ukrainians, with the last Russian troops leaving early on Friday.