A proposed sale of Israeli weapons including drones to Ukraine has been blocked for fear of antagonising Russia, Channel Two television reported on Monday.

The broadcaster said a Ukrainian delegation had visited Israel with a view to acquiring military hardware including drones to use against pro-Russian separatists.

It was not reported when the visit took place or when the decision to turn down the request was taken.

Israel's defence ministry had given the green light for the sale of pilotless aircraft produced by the company Aeronautics to Ukraine, but the foreign ministry then vetoed the sale.

Monday's television report said the ministry concluded that the sale risked causing anger in Russia and could provoke Moscow to sell more arms to Syria and Iran, the Jewish state's arch-enemy.

A defence ministry spokesman refused to comment on the report.

Ukraine's shaky truce was rattled further on Monday as warring rivals traded blame over the bloodiest day in the restive east since a ceasefire was signed on September 5.

Ukrainian government forces and pro-Russian separatists accused the other of violating the ceasefire, the first backed by both Kiev and Moscow since fighting erupted in April.