ANKARA, July 4 (Xinhua) -- The Turkey-Russia-Iran trilateral summit on Syria will be held in August in the capital Ankara, Turkish presidential spokesman Ibrahim Kalin said on Thursday.

The situation in Syria, including the transitional political process and the return of refugees, will be discussed comprehensively in the summit, Kalin told reporters, without giving the exact date.

The first trilateral summit was held in the Russia's Black Sea resort of Sochi on Nov. 22, 2017 to discuss progress made in the Astana peace talks and changes in de-escalation zones across Syria.

Meanwhile, Kalin said the second four-party summit of the leaders of Russia, Turkey, Germany and France is scheduled to be held in Istanbul in late August or early September, before the UN General Assembly.

"During the G20 summit it was agreed upon that a four-party summit on Syria just like the one from last year will be held in Istanbul hosted by our president," he was quoted by Anadolu Agency as saying.