Germany has decided to postpone plans to upgrade Turkish military tanks after they were spotted crossing the border into Syria as part of the assault on Efrin, Foreign Minister Sigmar Gabriel said.

In an interview with Spiegel published on Thursday, Gabriel said the Leopard tank upgrades would be postponed until a new government is formed amid concerns over the military conflict.

“The Federal Government is very concerned about the military conflict in northern Syria,” Gabriel said. “As far as the current discussions about armaments exports are concerned, it is clear to the Federal Government that we are not allowed to and will not deliver into areas of tension.”

“The federal government is in agreement,” he continued, “that we do not anticipate the outcome of the ongoing coalition negotiations and wait with the consultation of critical projects to the new formation of a government.”

Turkey had requested German upgrades to its Leopard 2 tanks to make them less vulnerable to improvised explosive devices, but lawmakers – including some from Angela Merkel’s own CDU party – protested the proposed deal after photos emerged over the weekend of them being used in the Efrin operation.

Turkey operates more than 350 Leopard tanks, although a number were damaged or destroyed by Islamic State in Syria.

Gabriel had been a proponent of the deal, which was announced the day before Turkey launched Operation Olive Branch.