The points of disagreement between Turkey and NATO allies now run from weapons deals with Moscow to developments in northern Syria, the eastern Mediterranean, Libya and back up to the Baltic states — encircling the nation that long played a key role as the bloc’s southeastern flank.

Speaking as he departed for the NATO summit in London Tuesday, Turkish President Recep Tayyip Erdogan reaffirmed he would oppose a defense plan for the Baltic nations and Poland unless the allies classify a Kurdish militia as a terrorist organization.

“If our friends at NATO do not recognize as terrorist organizations those we consider terrorist organizations … we will stand against any step that will be taken there,” Erdogan said, referring to the Kurdish-led People’s Protection Units (YPG) in northeast Syria against which Ankara launched a military operation in October.

The statements add to simmering tensions regarding burden-sharing and member states’ commitments to the alliance as it marks its 70th anniversary, and risk further unsettling relations in the face of growing threats from Russia and China.