ISTANBUL, Jan. 27 -- Turkish President Recep Tayyip Erdogan said Saturday that arms have been piling up in Syria under the pretext of fighting the Islamic State (IS) "although there were no jihadists left in the country."

Turkey has long blasted the United States for supplying arms to the People's Protection Units (YPG), the armed wing of Syria's Kurdish Democratic Union Party (PYD), as Ankara treats both as the Syrian branches of the Kurdistan Workers' Party (PKK) outlawed for its continued armed struggle against the Turkish state.

"Whenever we expressed this, they reacted by saying 'these are our partners'," Erdogan said in a televised speech in Istanbul, referring to Washington using the YPG as an ally in its fight against the IS.

"Although the whole world has seen that the boss of the terrorist organization in Syria is Qandil, it is only our ally who is not accepting this," Erdogan added, as the PKK is based in Iraq's Qandil Mountains.

The president stressed that it does not matter whether the terror group is called the IS, PKK, PYD or YPG.

Meanwhile, the Turkish presidency confirmed in a statement on Saturday that the U.S. would no longer provide the YPG with weapons, an irritant in U.S.-Turkey ties.

The Turkish military launched an operation against YPG-held Afrin in northwestern Syria on Jan. 20.

"When Turkey is doing its part for its own security and the peace of its brothers, it, of course, wants to realize this together with its allies," added Erdogan.