Armenia on Tuesday invited Turkey's leader to events next year marking the 100th anniversary of World War I-era massacres that Armenians say amounted to genocide, despite Ankara's fierce rejection of the term.
Relations between the two countries have long been soured by disputes over the massacres, in which Armenians say up to 1.5 million people were killed in what is now Turkey as the Ottoman Empire was falling apart.
"I officially invite the president of Turkey... to visit Armenia on April 24, 2015, to face striking evidence of the Armenian genocide," President Serzh Sarkisian said in a statement.
Turkey will hold a presidential election in August, after incumbent Abdullah Gul's seven-year term expires.
In April Turkish Prime Minister Recep Tayyip Erdogan for the first time offered his condolences over the 1915 massacres and mass deportations, calling them "our shared pain".
Armenia dismissed the statement, accusing Ankara of "utter denial" of its claims the killing constituted genocide, a view that is backed up by many countries.
"Official Ankara is taking new steps that are unprecedented in their form but unfortunately reflect its century-old policy of denial," Sarkisian said.
"The only possible step the Turkish authorities can take is to recognise the Armenian genocide."
Using both diplomatic levers and its widespread diaspora abroad, Armenia has long sought to win international recognition of the killings as genocide.
Turkey has fiercly rejected the term, arguing that 300,000 to 500,000 Armenians and at least as many Turks died in civil strife when Armenians rose up against their Ottoman rulers and sided with invading Russian troops.