Restoring the temporarily occupied parts of Donetsk and Luhansk regions will require around $10 billion, Ukrainian President Volodymyr Zelensky's economic advisor Oleh Ustenko said.

"Preliminary estimate: that's around $10 billion, which will be needed to restore the uncontrolled territory. That is 5-7 per cent of our GDP," Ustenko told The Donbas.Realities radio station on Saturday.

Once those areas have been reintegrated, it will be necessary to set up a fund with money from donors among others, he said.