By Will Vernon in Moscow & Samuel Horti in London
Youth Hekima News
Russian President Vladimir Putin has ordered his defence minister to impose a 36-hour ceasefire on the Ukrainian frontline, beginning on Friday.
The ceasefire, scheduled to start at 12:00 Moscow time (09:00 GMT), will coincide with the Russian Orthodox Christmas.
Mr Putin asked Ukraine to reciprocate, but Kyiv quickly rejected the request.
Ukrainian presidential adviser Mykhailo Podolyak said: "Keep hypocrisy to yourself."
The Kremlin statement appeared to stress that President Putin ordered his troops to stop fighting not because he was de-escalating - Putin never de-escalates - but because he had listened to an appeal from the head of the Russian Orthodox Church.
Patriarch Kirill had, earlier in the day, called for a Christmas truce to allow believers to attend church services for Orthodox Christmas.
The Russian Orthodox Church celebrates Christmas Day on 7 January, according to the Julian calendar.
A Kremlin statement said: "Taking into consideration the appeal by [Kirill], the president hereby instructs the minister of defence of the Russian Federation to impose a ceasefire regime along the entire line of contact in Ukraine" for the 36-hour period.
Mr Putin's order called on Ukraine to reciprocate so that the "large numbers of Orthodox believers [who] reside in areas where hostilities are taking place" could celebrate Christmas Eve on Friday and Christmas Day on Saturday.
In a statement on Twitter son after, said there could be no "temporary truce" until Russian forces withdrew from all the areas they had occupied.