KIEV (AFP) - Ukrainian President Petro Poroshenko on Saturday (May 13) cancelled his planned appearance at the Eurovision Song Contest final in Kiev after a shelling attack in the war-torn east reportedly killed four civilians.

The Kiev-appointed head of the conflict-riven Donetsk region said earlier Saturday that the deaths occurred when "Russian occupying forces" shelled an apartment bloc.

"Three women and one man was killed," Pavlo Zhebrivskiy wrote on Facebook.

The deaths marked the single biggest loss of civilian life since a new Easter truce in the three-year war went into effect on April 1.

The shelling attack was staged in Avdiivka - a devastated flashpoint suburb of the Russian-backed insurgents' de facto capital city of Donetsk.

Poroshenko said he was planning "to be at the contest final with (my wife) Marina and invited our fighters and people with disabilities to support Ukraine." "However due to the shelling of Avdiivka and the death of peaceful civilians, I took a decision to cancel my presence at the Eurovision final," he wrote on Facebook.

The latest casualties bring the number of Ukrainian soldiers and civilians who have been reported killed by officials this month to 14.

Ukraine accuses Russia of plotting and backing the conflict in which more than 10,000 have died - a charge Moscow flatly denies.

The war zone lies some 500 kilometres to the east of the capital Kiev where thousands of foreign tourists gathered to watch the annual televised song competition in which 42 nations took part.