Ankara is refusing to agree to a NATO defence plan for the Baltics and Poland over lack of political support for its fight against Kurdish forces in northern Syria, Reuters said on Tuesday citing four senior alliance sources.

Turkey has told its NATO envoy not to sign off on the plan and is calling on the alliance recognise the Syrian Kurdish People’s Protection Units (YPG) as terrorists in the formal wording, Reuters said.

Turkey views the YPG as a terrorist organisation due to its links to Kurdish insurgents in southeast Turkey. The country last month attacked the U.S.-allied forces following U.S. President Donald Trump’s abrupt withdrawal of 1,000 U.S. forces from northern Syria in early October.

Turkey’s NATO delegation was not immediately available for comment and the country’s defence and foreign ministries did not respond to requests for comment, Reuters said.

The report arrives amid looming questions over Turkey’s membership in the alliance following its purchase of the Russian S-400 missile systems. The decision of Turkey, a NATO member since 1952, to go through with the S-400 purchase this summer despite opposition from the alliance and the United States over security concerns has sparked reports of Ankara’s pivot toward Moscow.



NATO envoys are seeking formal approval by all 29 members of the alliance for the military plan to defend Poland, Lithuania, Latvia and Estonia in the event of a Russian attack, Reuters said.



Without Ankara’s approval, it said, it could become more difficult for the alliance to step up its defences in the Baltics and Poland quickly.



“They (the Turks) are taking eastern Europeans hostage, blocking approval of this military planning until they get concessions,” Reuters quoted one of the diplomatic sources as saying.

Another source told Reuters that Ankara’s behaviour was “disruptive”.

The plan for the Baltic states and Poland, drawn up at their request after Russia annexed Crimea from Ukraine in 2014, has no direct bearing on Turkey’s strategy in Syria, Reuters said.

The plan does, however, raise issues about security on all of NATO’s frontiers, it added.