The Kremlin issued a warning to Kurdish forces on Wednesday that they must withdraw from the Turkish border region immediately, or else “Syrian border guards and Russian military police officers will have to pull back,” leaving the Kurds to be “run over by the Turkish military machine.”

The Kurdish-led Syrian Democratic Forces (SDF) previously agreed to let Russian troops and the Syrian military into their territory to block the Turks from attacking vital areas such as the cities of Kobani and Manbij. The Russian Defense Ministry said on Wednesday morning that Russian military police units have arrived in Kobani to “facilitate the withdrawal of Kurdish YPG forces and their weapons.”

The Russians effectively threatened to withdraw that protection unless the Kurds pull back the militia groups seen as terrorists by Turkey.

The Kremlin taunted Kurdish commanders by saying they have been “betrayed and abandoned” by the United States, even though the Russians were threatening exactly the same type of withdrawal.

“The United States has been the Kurds’ closest ally in recent years. In the end, it abandoned the Kurds and, in essence, betrayed them. Now they prefer to leave the Kurds at the border and almost force them to fight the Turks,” said Kremlin spokesman Dmitry Peskov.

The Russian statement came hours after President Vladimir Putin met with Turkish President Recep Tayyip Erdogan in the Black Sea resort of Sochi and made a deal for joint policing of the 20-mile-deep “safe area” Turkey desires along its border with Syria.

“According to this agreement, Turkey and Russia will not allow any separatist agenda on Syrian territory,” Erodgan declared after the meeting, a reference to Turkey’s allegations that Syrian Kurdish militia groups are allied with the violent separatist PKK party in Turkey.

Putin said he explained the results of the Sochi summit to Syrian dictator Bashar Assad by telephone. According to the Kremlin, Assad “expressed his full support for the results of the work, as well as the readiness of the Syrian border guards, together with the Russian military police, to reach the Syrian-Turkish border.”

“The established status quo in the current Operation Peace Spring area covering Tel Abyad and Ras al-Ayn with a depth of 32 kilometers will be preserved,” said a joint statement from Sochi read by Russian Foreign Minister Sergei Lavrov and Turkish Foreign Minister Mevlut Cavusoglu. “Operation Peace Spring” is the name given by Turkey to its invasion of Syria.

“All YPG elements and their weapons will be removed from Manbij and Tal Rifat,” the statement declared, referring to the Kurdish militia.

Russia and Turkey said they would establish “a joint monitoring and verification mechanism” to ensure their requirements are met.

Turkish media reported on Wednesday that the withdrawal of YPG forces is under way, while the Turkish Defense Ministry said it has been informed that the withdrawal is complete. Turkey said it saw “no need” to resume hostilities given these developments.

U.S. President Donald Trump announced on Wednesday that the cease-fire in northeastern Syria is now effectively permanent and he would, therefore, lift sanctions against Turkey “unless something happens that we are not happy with.”