Germany and Turkey planned to discuss on 24 January Ankara’s cross-border offensive against a Kurdish militia in Syria, amid controversy over German-built tanks being deployed in the conflict.

According to Maria Adebahr, German foreign ministry spokeswoman, German ambassador Martin Erdmann and Turkish Defence Minister Nurettin Canikli were to talk about ‘how the Turkish operation is equipped'.

The German government has come under domestic pressure after battlefield images appeared to show Turkey deploying German-made Leopard 2 tanks in its offensive to oust Kurdish militants in northern Syria.

German conservative lawmaker Norbert Roettgen, who heads the parliamentary committee of foreign affairs, urged Foreign Minister Sigmar Gabriel to halt further arms deals with Turkey.

Roettgen said: ‘It is completely out of the question for Germany to increase the combat strength of the Leopard tanks in Turkey if the Turkish Army is going after the Kurds in northern Syria.’

Roettgen, a leading figure in Chancellor Angela Merkel's CDU party, said weapons deliveries to Turkey should instead ‘be banned due to the human rights situation and the dismantling of the rule of law in the country'.

Germany's criticism of the human rights situation in Turkey, particularly after the government's crackdown following a failed coup in 2016, badly strained ties between the NATO allies.

Relations have started to gradually thaw in recent weeks with the foreign ministers of both countries vowing to mend ties.

But Turkey's offensive against the Kurdish militia threatens to reverse the rapprochement with Germany, which is home to large ethnic Turkish and Kurdish minorities.

Berlin delivered 354 Leopard 2 (pictured) tanks to Turkey between 2006 and 2011.

Under the weapons deal sealed in 2005, Ankara is prohibited only from giving or selling the tanks to third parties without prior approval from Berlin, with no other restrictions on how the tanks are used.