(VOA) -- In Turkey, commemorations are being held to mark the mass killings of Armenians during World War I by Ottoman Turks. The killings, recognized as genocide by much of the international community, remains contentious, with Ankara strenuously claiming the deaths were the result of a civil war in which Turks also perished. Turkish-Armenian groups, along with nongovernmental organizations mainly in Turkey's largest city, Istanbul, are organizing a series of events to remember the deaths.

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On Tuesday, public ceremonies are planned outside some of the homes of 270 Armenian intellectuals, religious and civic leaders arrested in Istanbul on April 24, 1915. The detentions marked the start of the mass deportations and killings of Armenians across Turkey. As many as one-and-a-half million people were killed as the Ottoman Empire disintegrated, according to a version of events accepted by many historians. Until Turkey's ruling AK Party came to power in 2002, public discussion challenging the state's official version of events was forbidden. "There has been some tolerance by the state, they were not participating themselves, but they were allowing the commemorations, publications of books, articles and the gatherings and so on," said political scientist Cengiz Aktar. "But this progress has come to a halt, because of the very restrictive environment of free speech," Aktar added, referring to the current emergency rule, introduced after a failed 2016 coup. Analysts say campaigners for the recognition of the killings as a genocide are focusing their attention on U.S. President Donald Trump. "The only thing that might happen is Trump may pronounce the 'G' [genocide] word; we will see. It may happen; there are some indications Trump may pronounce it," said Aktar. "The American administration, the Senate, House of Representatives, are getting more and more nervous with Turkey; the president may come with the 'G' word tomorrow." On April 24, U.S. presidents deliver a speech to mark the mass killings of Armenians. Last year Trump, like his recent predecessors, sidestepped using the word genocide, instead, using the Armenian phrase, "Meds Yeghern," meaning great calamity. This month, more than 100 members of the U.S. Congress wrote to Trump, calling on the president to recognize the mass killings as genocide. U.S., Turkish relations Turkey has angered the U.S. recently over several issues, including Syria, the imprisonment of U.S. citizens and local employees of diplomatic missions, and Ankara's deepening ties with Moscow. "Compared to years past, Turkey's ability to influence Congress [against using the word genocide] has been vastly diminished, that is certainly true," said analyst Sinan Ulgen, a visiting scholar of Brussels-based Carnegie Europe. Ulgen suggests Ankara will be banking on Trump's sensitivity toward Turkey. "There is a sizable constituency on the part of the executive, including President Trump, who believes in and understands the value of Turkey," he said. "So, there are certainly efforts that want to re-establish a sense of balance and direction to the bilateral relationship." If Trump were to use the word genocide, observers suggest Erdogan will seize on the occasion to whip up nationalist sentiment and anti-Americanism as Turkey prepares for presidential and general elections in June. Ankara, however, is likely to be more concerned by any move by Congress to legislate the recognition of an Armenian genocide. "The Congress resolution is much more binding than a presidential statement," said political scientist Aktar. "Ankara will be more concerned and irritated, and up until now Congress never passed a resolution. But with the anti-Turkish feelings, it may pass; there is something rumored to be in the pipeline, but not now." Growing recognition In recent years, growing numbers of countries have recognized the Armenian mass killings as a genocide. Given the growing tide of recognition, experts suggest Ankara's reaction has become more restrained. "The Dutch parliament recently passed an [Armenian genocide] resolution; all we saw were a couple of strong words and nothing else," said international relations expert Soli Ozel of Istanbul's Kadir Has University. "Turkey's government has decided that it is better to keep calm rather than raise hell every single time something important or unimportant happens. It may very well be the same as with the Americans; but, the American acceptance of a genocide is significantly more important than any other country," Ozel added. If Congress recognized the Armenian killings as genocide, experts suggest the move could open the door to numerous legal cases against Turkey by relatives of those killed. Genocide does not have a legal statute of limitations. Even though Ankara lost many of its allies in Washington, it may still retain some support. "The Turkish side tried to keep relations with the Jewish or pro-Israeli lobbies pretty good," Ozel said. "Every time the president [Erdogan] visited the United States, he made sure that he met with the Jewish organizations, so maybe they are on board, and if they are on board, you have a fighting chance."