Russian President Vladimir Putin is warning that more military aid for Ukraine would further destabilize the situation and aggravate the humanitarian crisis.
Putin talked by telephone with French President Emmanuel Macron and German Chancellor Olaf Scholz on Saturday.
The Kremlin says Putin warned about the dangers of what it described as pumping up Ukraine with Western weapons.
Macron and Scholz urged Putin to lift the blockade of Ukrainian ports on the Black Sea. Putin reportedly said that Moscow is ready to help find options for unhampered exports of grain, including exports of Ukrainian grain from the Black Sea ports.
Putin insisted that sanctions against Russia should be lifted to prevent a global food crisis.
Russian forces are trying to besiege Severodonetsk, which is seen as Ukraine's last stronghold in the Luhansk region.
Russia's defense ministry claimed on Saturday that its military is in full control of Lyman, a strategic railway hub in the neighboring Donetsk region. It's about 40 kilometers west of Severodonetsk.
Britain's defense ministry says Russian forces could use Lyman as a foothold to make their way toward Severodonetsk.