Iranian President Mahmoud Ahmadinejad will visit Turkey on Dec 17 upon an invitation from Prime Minister Recep Tayyip Erdoğan, but the visit comes increased tension due to the two countries’ differences over Syria, as well as difficulties stemming from sanctions against Tehran, Hurriyet Daily News reported.

Erdoğan and Ahmadinejad are expected to discuss a wide range of issues, including Syria and Turkey’s decision to further cut the oil it purchases from Iran as part of Washington’s sanctions. But Turkey has said it will not give up its much-publicized “gold-for-gas” trade with Iran despite the new package of sanctions imposed by the U.S.