Turkish Foreign Minister Mevlut Cavusoglu said on Tuesday that any move by U.S. President Joe Biden to recognise the 1915 mass killings of Armenians by the Ottoman Empire as a genocide will further harm already strained ties between the NATO allies. Turkey accepts that many Armenians living in the Ottoman Empire were killed in clashes with Ottoman forces during World War One, but contests the figures and denies that the killings were systematically orchestrated and constitute a genocide. Commemorations of the killings are held around the world each April 24. For decades, measures recognizing the Armenian genocide, stalled in the U.S. Congress and U.S. presidents have refrained from calling it that, stymied by concerns about relations with Turkey and intense lobbying by Ankara. Asked in an interview with broadcaster Haberturk about whether Biden would recognise the killings as a genocide amid reports he would be the first U.S. president to do so, Cavusoglu said the United States "needs to respect international law". "Statements that have no legal binding will have no benefit, but they will harm ties," Cavusoglu said. "If the United States wants to worsen ties, the decision is theirs," he said. In 2019, the U.S. Senate passed a non-binding resolution recognizing the killings as a genocide, in a historic move that infuriated Turkey Ties between Ankara and Washington have been strained over a host of issues, from Turkey"s purchase of Russian S-400 defence systems - over which it was the target of U.S. sanctions - to policy differences in Syria, human rights and legal matters. Turkish President Tayyip Erdogan established a close bond with former U.S. President Donald Trump, but he has yet to speak to Biden since he became president on Jan. 20. Officials from Turkey and the United States have held talks since Biden"s administration took office.