A new round of international talks on ending the war in Syria will be held in New York, just weeks before the planned start of a ceasefire and peace negotiations, UN Secretary-General Ban Ki-moon said Thursday, according to AFP . Ban did not announce a date for the meeting, but diplomats said it was likely to be held on December 18. "Member-states are very closely coordinating to have the third Vienna process meeting here in New York," Ban told reporters. "I'm looking forward to that," he added. Diplomats from 17 countries have held two meetings in Vienna to agree on a roadmap to end the nearly five-year war in Syria that has left 250,000 dead and triggered a refugee crisis in Europe. In the first round at the end of October, the United States and Russia "agreed to disagree" about the role of Syrian President Bashar Al-Assad, whom Russia backs but the United States does not. Following the second round, however, Secretary of State John Kerry said that Syria could be weeks away from a "big transition". Kerry said there was now a "genuine process with possibilities" to unlock the war in Syria. The international talks bringing together for the first time key players Russia, the United States, Iran and Saudi Arabia mark the most significant push to date for a settlement. There had been concerns that the row between Russia and Turkey over the downing of a Russian fighter plane could have jeopardized the talks, but Ban's announcement Thursday indicated that the peace effort was on track. At the last meeting on November 14, countries agreed on a path to elections in 18 months and a political transition within six months. Ban said the aim was to declare a nationwide ceasefire and launch political talks between the Syrian government and the opposition in early January. "The Vienna peace process has created new momentum," Ban said. "We are working to launch an initiative in early January that would involve both intra-Syrian political talks and a nationwide ceasefire." Ahead of the New York talks, Saudi Arabia is due to host a meeting of Assad's armed and political opponents, although no date has been announced. Jordan is preparing a list of opposition groups who will have a seat at the negotiating table, making the distinction between those with a political stake in Syria's future and "terrorists" who will be left out. Ban stressed the need for "very practical and realistic progress" in the Syria peace effort after a string of diplomatic failures allowed the war to grind on. AFP contributed to this report.