Russia says peace talks haven’t yet advanced to a stage to allow Vladimir Putin and Volodymyr Zelenskyy to meet.
Both countries have held several days of negotiations, including a day in Istanbul, Turkey earlier this week.
After those talks, Russia said it would “radically reduce” its military activity focused on the Ukrainian cities of Kyiv and Chernihiv.
Mr Fomin said the decision to pull back was taken in the interest of creating mutual trust and the necessary conditions for further talks to take place.
Mr Zelenskyy confirmed on Saturday that Russian forces were withdrawing from some parts of Ukraine at a “slow but noticeable" rate.
Russian President Vladimir Putin
PA
Missile strikes continue across part of Ukraine
GLEB GARANICH
Ukrainian negotiator David Arakhamia told Ukrainian television on Saturday that a draft deal following recent walks was advanced enough to allow consultations between Mr Putin and Mr Zelenskyy.
But Russia does not share the same optimism, its chief negotiatior Vladimir Medinsky said, adding that Moscow’s position on Crimea and Donbas remains unchanged.
"Unfortunately, I don't share Arakhamia's optimism," Mr Medinsky said. "Moreover, Ukrainian diplomatic and military experts lag far behind on confirming even those agreements which were already reached at the political level on the draft text.”
He added: "The draft agreement is not ready for submission to a meeting at the top.”
His comments came just hours before the Russian Defence Ministry said missile strikes by its military destroyed an oil refinery and three storage facilities near the Ukrainian Black Sea port of Odesa on Sunday.
The ministry said the facilities were used by Ukraine to supply its troops near the city of Mykolaiv.
The war entered its 39th day on Sunday.
