Turkey says it is recalling its ambassador to Austria after parties represented in parliament issued a joint declaration calling the massacre of ethnic Armenians in the Ottoman Empire 100 years ago genocide.
The six parties signed the declaration on April 22 and held a minute of silence in memory of the victims.
"It is our duty to acknowledge and condemn these terrible events as genocide because of our historical responsibility -- the Austro-Hungarian monarchy was an ally of the Ottoman Empire during World War I," the declaration reads.
The Turkish Foreign Ministry said "Turkey and the Turkish nation will never forget this slander against its history."
The slaughter and deportation of up to 1.5 million Armenians by Ottoman Turks in 1915 is considered by many historians and several nations as genocide.
Turkey objects, saying that Armenians died in much smaller numbers and because of civil strife rather than a planned Ottoman government effort to annihilate the Christian minority.