Russia and the Syrian Kurdish YPG militia have signed a bilateral agreement establishing a Russian military base in northwestern Syria, a YPG spokesman said Monday. The Russian Defense Ministry issued a statement, saying it had no plans for additional bases in Syria but that it had set up a “reconciliation center” in the area.

The agreement, being described as a first of its kind, also provides for Russia to train YPG fighters, YPG spokesman Redur Xelil.

The agreement, which took effect Monday, is meeting with opposition from Turkey, which said it would not allow a “terror region” to be established in northern Syria, Reuters reported.

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Though the YPG is allied with both the U.S. and Russia against the Islamic State group, Turkey considers the YPG an arm of the Kurdistan Workers Party, which it has labeled a terrorist organization because of its efforts to establish an autonomous Kurdish state.

The YPG-Russia agreement was finalized Sunday, Xelil told Reuters. He said Russian troops already have arrived in the area.

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"The Russian presence ... comes in agreement between [the YPG] and the Russian forces operating in Syria in the framework of cooperation against terrorism and to help train our forces on modern warfare and to build a direct point of contact with Russian forces," Xelil said in a written statement.

“There are no plans to deploy new Russian military bases on the territory of Syria,” the Russian Defense Ministry said in a statement.

The reconciliation center will separate the Kurds from Turkish-backed fighters, AMN Al-Masdar News reported.

Turkish Deputy Prime Minister Numan Kurtulmus told an Ankara news conference both the U.S. and Russia are aware of Turkey’s position on the Kurdish fighters. Turkey, with the help of allies within the Free Syrian Army, has been trying to keep the YPG from gaining terrority to create a contiguous Kurdish area along the Syria-Turkey border.

The YPG is hoping to expand its force by two-thirds to more than 100,000 fighters and form a more traditional army, Xelil said.

Russia has been bolstering the regime of Bashar Assad since 2015, providing air cover for Syrian troops. Though Damascus and the Kurds have been at odds for many years, the Kurds have been largely neutral in the 6-year-old Syrian civil war.

Anti-ISIS forces are planning to begin an assault against Raqqa, the terrorist group’s de-facto capital in Syria, with the YPG planning to fight alongside Arab forces.

Pro-government jets — it was unclear whether they were Russian jets or Syrian — bombed opposition-held areas of Damascus Monday, a day after rebels staged a surprise assault targeting sites in the Old City. Rebel groups allied with former al Qaeda affiliate Jabhat Fateh al-Sham hit government positions east of the capital Sunday but were driven back by nightfall, Al Jazeera reported.

Among the buildings damaged in Monday’s assault was one belonging to the Russian Embassy, Syrian state television reported.