A delegation of German lawmakers, accompanied by a senior NATO official, will visit German soldiers serving at an air base in Turkey on Sept. 8 as part of a NATO trip, Turkey’s foreign ministry said on Thursday.

NATO’s Deputy Secretary General Rose Gottemoeller will lead the delegation which will reportedly consist of seven members of Germany’s Parliamentary Committee.

Between 20 and 30 German troops are currently stationed at the base in support of NATO’s operations against the Islamic State in Syria.

A row over access to German soldiers at Turkish bases has heightened tensions between the NATO allies and fueled a wider row.

Turkey on July 14 refused to give permission to seven German lawmakers who were planning to visit German soldiers stationed at a NATO base in the central Turkish province of Konya, after Germany did not allow Turkish President Recep Tayyip Erdoğan to address Turkish expats when he visited Hamburg for the G20 summit.

Germany’s armed forces are under parliamentary control and Berlin insists lawmakers must have access to them.

Ankara’s repeated refusals to allow lawmakers visit German soldiers at Turkey’s Incirlik air base prompted Berlin to relocate those troops to Jordan.