Russian President Vladimir Putin said on Wednesday that he expected the situation to "stabilise" in Ukrainian regions annexed by the Kremlin after Moscow suffered military setbacks and lost several key towns to Kyiv.
He also ordered his government to seize control of Europe's largest nuclear power plant in the Russian-controlled region of Zaporizhzhia with IAEA head Rafael Grossi en route to Kyiv for consultations on the facility.
Ukraine earlier claimed victories over Russian troops in the eastern region of Lugansk as the Kremlin vowed to recapture territory lost in a lightning Ukrainian counteroffensive.
In recent weeks, Ukraine's forces, bolstered by Western weapons, have wrested Russian troops out of a string of towns and villages in the southern Kherson region and the eastern separatist strongholds of Lugansk and Donetsk.
"We are working on the assumption that the situation in the new territories will stabilise," Putin told Russian teachers during a televised video call.
Just hours earlier, the Ukrainian-appointed head of Lugansk Sergiy Gaiday announced that the "de-occupation of the Lugansk region has already officially started".
A senior Russian lawmaker called on military officials to tell the truth about developments on the ground in Ukraine following the string of bruising defeats.
"We need to stop lying," the chairman of the lower house of parliament's defence committee, Andrei Kartapolov, told a journalist from state-run media.
"The reports of the defence ministry do not change. The people know. Our people are not stupid. This can lead to loss of credibility."
Putin on Wednesday signed into legislation his annexation of four Ukrainian territories – including Lugansk – as the European Union agreed a new round of sanctions against Moscow in response.
Kremlin spokesman Dmitry Peskov said Moscow would take back land it lost to Kyiv within the annexed regions, vowing they would be "Russian forever and will not be returned".
Putin initially inked agreements with the Moscow-installed leaders of the four regions to become subjects of the Russian Federation, despite condemnation from Kyiv and the West.
The four territories – Donetsk, Kherson, Lugansk and Zaporizhzhia – create a land corridor between Russia and the Crimean peninsula, which was annexed by Moscow in 2014.
Together, the five regions make up around 20 percent of Ukraine. (AFP)