Russia plans to confer with residents in two Moscow-annexed regions in Ukraine while determining the exact borders of the areas to be integrated into Russia, the Kremlin said Monday.

"We are going to continue to consult the populations of these regions," Kremlin spokesman Dmitry Peskov said referring to the southern Kherson and Zaporizhzhia regions that are partially controlled by the Ukrainian military.

"No doubt, any configuration will depend only on the will of the people who live in a particular territory," he said.

President Vladimir Putin last week signed legislation integrating the regions into Russia -- along with the Donetsk and Lugansk regions -- but the Kremlin did not specify whether Russia would formally annex the territory its forces didn't control.

In February, Putin recognised the independence of the so-called Donetsk and Lugansk republics within borders that rebel fighters did not have control over.

Ukraine's forces in recent days have even been clawing back territory that Russian forces controlled in the annexed territories, particularly in Donetsk and Kherson.