Pope Francis has provoked the anger of the Turkish government with his denunciation of the mass killings of Armenians during the World War I as a "genocide," with Turkey blasting his "crusader mentality" on Sunday.
At the start of his three-day trip to Armenia on Friday, Francis used the controversial term to describe the killings of up to 1.5 million Armenians by Turkish Ottoman troops during 1915-16.
Turkey strongly denies the term "genocide," saying the number is inflated.
When Francis used the term a year ago, during a special remembrance Mass in St Peter's Basilica, Turkey recalled its ambassador and accused the pope of speaking "nonsense."
The pope's latest declaration was "very unfortunate" and testament to the Holy See's "crusader mentality," Turkey's Deputy Prime Minister Nurettin Canikli was quoted as saying by the Anadolu news agency.
"The declaration is not objective," Canikli said.
However, the Vatican had emphasised the pope neither wanted nor expected a dispute with Turkey over the issue.
Before travelling back to Rome from Armenia on Sunday, Francis was due to release a peace dove outside a church near the closed Turkish border.
Francis on Saturday had called on neighbours Armenia and Turkey to lay aside their differences and also expressed his hopes for peace in the Caucasus region during an ecumenical prayer service in the Armenian capital Yerevan.
"May God bless your future and grant that the people of Armenia and Turkey take up again the path of reconciliation, and may peace also spring forth in Nagorno-Karabakh," the 79-year-old pontiff said.
As well as with Ankara, Armenia has difficult relations with Azerbaijan, another neighbour. The two nations have rival claims to Nagorno-Karabakh, an Armenian enclave in Azeri territory where violence broke out in April, killing at least 120 people.
Armenia has a special place in Christianity because it was the first nation to adopt it as a state religion, in 301 AD. John Paul II was the last pope to visit it in 2001, to mark the 1,700th anniversary of the country's conversion.