Reports of an Israeli "suicide drone" being used by Azerbaijan's army in the recent fighting in the contested enclave of Nagorno-Karabakh has caused controversy in the Jewish state and sparked protests from Armenia.

Israel has not confirmed or denied it sells the Harop drone to Azerbaijan.

The Harop is a "loitering munition" - a flying bomb that can take off and position itself over hostile territory. It is designed by Israel Aerospace Industries to home in on radiation-emitting targets, usually anti-aircraft radars and missile batteries.

In recent weeks, the Armenians have claimed that the drone has been used in the fighting that has broken out in Nagorno-Karabakh, the Armenian-controlled enclave within Azerbaijan's territory. Armenian officials backed up their claim by publishing footage of a drone resembling the Harop. They also alleged that a Harop was used to bomb a bus, killing seven Armenian "volunteers".

Israel has a strategic alliance with Azerbaijan, a secular Muslim country and a neighbour of Iran which supplies around half of Israel's oil.

Israel has never officially confirmed arms sales to Azerbaijan but, according to foreign media reports, these have included drones and radar systems.

Last week, Armenia's ambassador to Israel lodged an official complaint in Jerusalem over the arms sales and the chairman of the opposition Meretz Party sent this week a letter to Defence Minister Moshe Yaalon demanding that Israel delay a planned shipment of more drones to Azerbaijan until it receives a commitment that these will not be used against the Armenians.