Turkey expects US President Donald Trump to stick to his promise not to supply weapons to the Syrian Kurdish militia fighting Islamic State jihadists, Turkish Foreign Minister Mevlut Cavusoglu said on Saturday.

"It is our most natural right to expect Trump to keep his promise," Cavusoglu said in televised comments in the southern Mediterranean resort of Antalya.

"Naturally, as I said yesterday, we want to see this applied," he added.

Ankara's top diplomat on Friday said Trump had told Turkish President Recep Tayyip Erdogan that he has given an order that weapons should no longer be supplied to the Kurdish YPG militia, during a phone call between the leaders.

The YPG is the Kurdish Peoples' Protection Units militia in Syria, which Washington views as the most effective fighting force on the ground against the IS extremist group.

However, Ankara sees the YPG and its political wing, the Democratic Union Party (PYD), as "terrorists" linked to the outlawed Kurdistan Workers' Party (PKK).

Proscribed by Turkey and its Western allies including the US as a "terror" group, the PKK has waged an insurgency inside Turkey since 1984.

But the White House was less explicit about the US military's intentions towards the YPG, only saying that Trump informed Erdogan "of pending adjustments to the military support provided to our partners on the ground in Syria".

In recent months, the YPG has recaptured territory from IS, including the former de facto IS capital of Raqa in northern Syria.

Ties between Washington and Ankara have been tense since the administration of former president Barack Obama over US support for the YPG and also the failure to extradite Pennsylvania-based cleric Fethullah Gulen, who Ankara accuses of masterminding last year's failed coup to overthrow Erdogan.

Gulen vehemently denies the charges.