Turkey, a close ally of Azerbaijan, shut down its border with Armenia in 1993, in a show of solidarity with Baku, which was locked in a conflict with Armenia over the Nagorno-Karabakh region.
In 2020, Turkey strongly backed Azerbaijan in the six-week conflict with Armenia over Nagorno-Karabakh, which ended with a Russia-brokered peace deal that saw Azerbaijan gain control of a significant part of Nagorno-Karabakh.
Turkey and Armenia also have a more than century-old hostility over the deaths of an estimated 1.5 million Armenians in massacres, deportations and forced marches that began in 1915 in Ottoman Turkey. Historians widely view the event as genocide.
Turkey vehemently rejects the genocide label, conceding that many died in that era, but insisting that the death toll is inflated and the deaths resulted from civil unrest.