ANKARA, Turkey (AP) — Turkish Prime Minister Recep Tayyip Erdogan has said he no longer holds “direct” telephone conversations with U.S. President Barack Obama, suggesting a rift between the leaders who were once close.

In an interview with Turkey’s ATV television late Monday, Erdogan said that “in the past, I used to call him directly. Because I was not able to get direct results on Syria, now our foreign ministers talk to each other.”

Erdogan did not elaborate. But the Turkish leader is known to have been frustrated by U.S. reluctance for a military involvement in Syria to end the violence there.

Erdogan told ATV he speaks with Vice President Joe Biden to discuss Iraq.

In the past, Obama cast Turkey as a model democracy and the two would frequently talk by telephone.

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