Turkish President Recep Tayyip Erdoğan accused Kurdish groups on Saturday of trying to seize control of northern Syria, saying Ankara would not allow this to happen.

In a speech in Southeast Turkey, Erdoğan also blasted Russian President Vladimir Putin for hosting Syrian President Bashar al-Assad earlier this week, in comments that were his most critical yet towards his Russian counterpart.

Erdoğan criticized Putin for hosting Assad in Moscow earlier this week, questioning how he could "welcome on a red carpet someone who has spilled the blood of 370,000 people." Erdoğan spoke during the opening ceremony of Hasan Kalyoncu University in the southeastern province of Gaziantep.

Assad flew to Moscow on Tuesday evening to thank Putin for his military support, his first foreign visit since the start of the Syrian war in 2011.

The surprise trip came three weeks after Russia launched a campaign of air strikes against Islamist militants and rebels in Syria that has bolstered Assad's forces.

On northern Syria, Erdoğan denounced the merging of the Syrian town of Tel Abyad last week into an autonomous political structure created by the Kurds.

"All they want is to seize northern Syria entirely," Erdoğan said. "We will under no circumstances allow northern Syria to become a victim of their scheming. Because this constitutes a threat for us, and it is not possible for us as Turkey to say 'yes' to this threat."

Tel Abyad, on the border with Turkey, was captured in June from the Islamic State in Iraq and the Levant (ISIL) by the Kurdish People's Protection People (YPG) militia with help from US-led air strikes. Last week, a local leadership council declared it part of the system of autonomous self-rule established by the Kurds.

Syrian Kurds have established three autonomous zones, or "cantons," across northern Syria since the civil war broke out in 2011. They deny aiming to establish their own state.

Turkey is alarmed by territorial gains for the Kurds in Syria's civil war, which it fears could stir separatism among its own Kurdish minority. For the past three decades Ankara has been trying to end an insurgency by fighters of the terrorist Kurdistan Workers Party (PKK), which is classified as a terrorist organization by the United States and European Union.

The PKK has been staging almost daily attacks in the Southeast since July, when a cease-fire fell apart.

Turkey accuses the Syrian Kurds' political arm, the Democratic Union Party (PYD), of deep links to the PKK. It has been incensed by the role the Kurds have carved out for themselves, with US support, in the fight against ISIL in northern Syria.

Erdoğan also slammed countries who provided assistance to the PYD, although he did not name them, and said it harbored 1,400 PKK members.

Earlier this month, the Kurdish YPG militia announced a new alliance with small groups of Arab fighters, and the group was air-dropped small arms and ammunition by US forces in northeast Syria.

Washington has indicated it could direct funding and weapons to Arab commanders on the ground who cooperate with the YPG.

Today's Zaman