Russia wants to create demilitarised buffer zones inside Ukraine around areas it has annexed, an ally of President Vladimir Putin said on Friday, saying it might be necessary to push deeper into Ukraine if such zones cannot be set up.
More than a year into Russia's invasion of Ukraine, Putin's core war aims remain unfulfilled despite Russian control of nearly a fifth of the country.
Neither side shows any sign of laying down arms. Hundreds of thousands of Russian and Ukrainian soldiers have been killed or seriously wounded, according to Western military estimates.
Former President Dmitry Medvedev, who casts himself as Putin's most publicly hawkish official, said Russia needed demilitarised corridors around the areas it is claiming - and which Ukraine says it will never accept Russian control of.
"We need to achieve all the goals that have been set to protect our territories, that is the territories of the Russian Federation," Medvedev, who is deputy chairman of Russia's Security Council, said in an interview with Russian media posted on Telegram.
We need to "throw out all the foreigners who are there in the broad sense of the word, create a buffer zone which would not allow the use of any types of weapons that work at medium and short distances, that is 70-100 kilometres, to demilitarise it," Medvedev said.
Russia would have to push further into Ukraine if such zones were not established, he said, taking Kyiv the capital or even the Western Ukrainian city of Lviv. Ukraine says it will never accept Russian occupation of its land.
"Nothing can be ruled out here. If you need to get to Kyiv, then you need to go to Kyiv, if you need to get to Lviv, then you need to go to Lviv in order to destroy this infection," said Medvedev.
Medvedev said on Friday that Russia was not planning to enter into a direct conflict with NATO and was interested in resolving the Ukraine crisis through talks, the Interfax news agency reported.
However, he warned that any Ukrainian attempt to take the Crimean peninsula - which Moscow annexed in 2014 - would be grounds for Russia to use "absolutely any weapon" against Kyiv in response.
Russia currently controls around 17-18% of Ukraine, including a swathe of land in the east and along the Azov and Black Sea coastline as well as Crimea which Russia annexed in 2014.
The grinding artillery war between two well-dug-in and well-supplied armies has been costly for Russia and Ukraine, which is supported by the United States and major European powers.
Russia insists it will achieve all of its war aims and has cautioned the West against testing its resolve. The West says that what CIA Director William Burns calls Putin's "hubris" will be pierced by battlefield defeat in Ukraine.
