Istanbul: Etyen Mahcupyan, a well-known ethnic Armenian writer, has retired as chief adviser to Prime Minister Ahmet Davutoglu as Turkey prepares for the 100th anniversary of the massacre of Armenians by Ottoman Turkish forces.

The centenary has stirred controversy in Turkey, with President Tayyip Erdogan rebuffing statements from Pope Francis and the European Parliament this week that the First World War killings of up to 1.5 million Armenians amounted to genocide.

Mahcupyan, whose appointment last October drew praise as a sign of Turkey’s commitment to minority rights, said his departure had nothing to do with the row. He said he retired in March after turning 65, the mandatory retirement age for civil servants, and still advises Davutoglu informally.

But the announcement of his departure, which was confirmed by the prime minister’s office on Thursday, came as he faced criticism by some in the government for reiterating his long-held view that the 1915 killings amounted to genocide. It was not clear why the announcement took more than a month.

“Mr Mahcupyan is no longer the chief adviser of our prime minister. His duties have ceased due to his retirement,” a source in Davutoglu’s office said.

“He was a figure whom our prime minister has consulted with and valued prior to him becoming an adviser, and this relationship will continue. But he no longer holds the official title of chief adviser.”

Earlier on Thursday, Turkey’s EU affairs minister, Volkan Bozkir, said Mahcupyan’s view that a genocide took place 100 years ago was unsuitable for a prime minister’s adviser.

“I consider his statement a personal one, made as a Turkish citizen. Of course, this perspective does not become a Turkish citizen either. Perhaps he will have a chance to reconsider his assessment,” Bozkir said in an interview with CNN Turk.

Muslim Turkey agrees that Christian Armenians were killed in clashes with Ottoman forces that began on April 24, 1915, when large numbers of Armenians lived in the empire ruled by Istanbul, but denies that this amounted to genocide.

Armenia, most Western scholars and several foreign legislatures refer to the mass killings as genocide.

On Sunday, Pope Francis triggered a diplomatic row with Ankara by calling the killings “the first genocide of the 20th century”. His remarks prompted Turkey to summon the Vatican’s ambassador and to recall its own.