ISTANBUL, Jan. 25 (Xinhua) -- Turkish Foreign Minister Mevlut Cavusoglu said Thursday that Turkey is not going to discuss the issue of building a safe zone in Syria with the U.S. until trust will be re-established between the two allies.

"We need to re-establish trust first with the U.S. in order to discuss building a safe zone in Syria or any other serious issues in a sincere manner," Cavusoglu pointed out at a press conference in Istanbul.

Cavusoglu said U.S. Secretary of State Rex Tillerson has suggested Ankara to build a 30 km safe zone in northern Syria along Turkey's border after Turkey launched a military operation in Syria's Afrin.

He noted trust between the two countries was damaged, as the U.S. has not been keeping its promises to Turkey.

"President Donald Trump said last night that his country stopped supplying arms to the YPG (the People's Protection Units)," Cavusoglu mentioned, referring to the phone conversation between the Turkish and U.S. presidents held on Wednesday.

"We have to see that in practice," he stressed.

Turkey has launched a military offensive, dubbed Operation Olive Branch on Jan. 20 against the YPG, which Turkey considers as the offshoot of the outlawed Kurdistan Workers' Party(PKK).

Turkish Prime Minister Binali Yildirim said last Sunday that the military operation aimed to establish a 30-km-deep security zone in Syria's Afrin.