NATO Secretary General Jens Stoltenberg said Monday he has “serious concerns” over actions by member state Turkey, but insisted the alliance was an important platform for resolving disputes involving Ankara, Arab Weekly reports.

Turkey has drawn the ire of some of its allies in the 30-nation grouping over its stance in a maritime territorial dispute with fellow NATO member Greece and its role in the conflicts in Syria, Libya and Nagorno-Karabakh.

NATO foreign ministers will gather next week in Brussels for the US-backed alliance’s first face-to-face meeting involving Biden’s team.

NATO has long tried to smooth over internal disputes with Turkey — pointing to the role Ankara has played in housing millions of refugees from Syria and in fighting the Islamic State (ISIS) extremist group.

The alliance last year set up a “de-confliction mechanism” to try to avoid clashes between Turkey and Greece as tensions spiked over the eastern Mediterranean and the standoff has since calmed.