Ukraine said on Saturday one of its soldiers was killed in fighting with pro-Moscow separatists, as the U.S. again warned Russia against any attacks on the country.
In his New Year’s Eve address, Mr. Zelensky said ending the war in the east remains his “main goal”.
“One serviceman of the Joint Forces was fatally wounded,” the army said in a statement.
It also added that separatists had launched three attacks within 24 hours, using grenade launchers and small arms.
The army gave no further details of how the soldier was killed.
Tensions with Moscow have soared in recent months, with Russia massing troops near Ukraine’s borders.
The West has accused the Kremlin of planning an invasion.
On December 22 international monitors said Russia and Ukraine had agreed to restore a ceasefire, but as early as the next day Kiev and separatists accused each other of new violations. The soldier’s death on Saturday was the first since the truce was agreed.
All previous ceasefires crumbled.
Kiev has been battling a pro-Moscow insurgency in two breakaway regions bordering Russia since 2014, when the Kremlin annexed Ukraine’s Crimean peninsula.
