The secretary of Ukraine's National Security and Defense Council (NSDC), Andriy Parubiy, has admitted that martial law could soon be declared in the country's eastern region.

"I do not rule out that there may come a time when it will prove necessary to declare martial law," Parubiy said at a press briefing on Friday, adding that he was speaking about the Donetsk and Luhansk regions.

NSDC has already drafted a document that permits the introduction of martial law in these parts of the country, he said.

"It is a large-scale document, which includes both a presidential decree and new coordination and command arrangements for our units in this new coordinate system," the official said.

Parubiy also informed reporters that measures to declare martial law would require several days, during which all the necessary changes should be made to the structure of the country's security services.

"I do not rule out that the issue of martial law will appear on the agenda of our state, the agenda of NSDC," he said.