US Secretary of State Mike Pompeo paid a fraught visit to Istanbul on Tuesday that included no official meetings and an agenda focused on religious freedoms that Ankara dismissed as "irrelevant".
Relations between Washington and its strategic NATO ally have remained strained despite a personal friendship between US President Donald Trump and his Turkish counterpart Recep Tayyip Erdogan.
A group of 20 to 30 Turks shouted "Yankee go home!" as the evangelical Christian Pompeo headed in for a meeting with the Patriarch Bartholomew I of Constantinople -- the spiritual leader of the Greek Orthodox world -- to express his "strong position" on religious freedoms.
Pompeo had publicly chided Erdogan's controversial conversion of Istanbul's emblematic Hagia Sophia monument into a mosque in July.
"An incredible privilege to be here," Pompeo told the patriarch.
The foreign ministry said ahead of Pompeo's arrival that the US should "first look in the mirror" before making an issue of the "completely irrelevant" subject of the freedom of faith in Turkey.
- Preparing for Biden -
Pompeo's seven-nation tour has been complicated by his unabashed support of Trump's unsubstantiated claim of election fraud -- and attempts by US allies to position themselves for Joe Biden's incoming presidency.
The US diplomat's two-night stay in Paris included a meeting with President Emmanuel Macron but no press conference that usually follows such talks.
Yet the Turkish leg looked destined for problems from the start.
Officials said Pompeo wanted to visit Istanbul to see the patriarch and was only ready to meet Erdogan and Turkish Foreign Minister Mevlut Cavusoglu on the condition they come to him from the capital Ankara.
A meeting had seemed possible after intense negotiations before the talks fell apart.
"This was a scheduling issue," a senior US official said.
"President Erdogan's schedule shifted and made it impossible to fit the parameters that from the very beginning we had set out."
It is difficult to gauge whether the election of Biden -- whom Erdogan congratulated three days after his victory was called by US media -- played a role in the imbroglio.
But it meant that Pompeo failed to discuss with Turkish officials the very problems he pointed to Monday after a meeting in Paris with Macron.
- Sanctions -
"President Macron and I spent a lot of time discussing Turkey's recent actions and we agreed they are very aggressive," Pompeo told the French daily Le Figaro.
Macron has sparred with Erdogan on a range of regional issues and shares Pompeo's mistrust of Turkey's robust foreign policy stance.
Pompeo said he and Macron touched on their mutual suspicion that Turkey "deployed Syrian forces" to help Azerbaijan in its six-week war with Armenia over the disputed Nagorno-Karabakh enclave.
"We also mentioned its action in Libya where it also sent forces from third party countries, and its action in the eastern Mediterranean. I could continue this list," Pompeo said.
The issues add to the dispute over Turkey's defiant acquisition of Russia's advanced S-400 anti-missile systems last year.
The US Congress has approved sanctions on Ankara for the purchase but Trump has given Turkey a reprieve.
"Sanctions is very much something that is on the table", the US State Department warned last month.
The visit coincides with the publication of a New York Times report saying Trump last week asked his aides -- including Pompeo -- about the possibility of striking Iran's nuclear facilities.
The officials "dissuaded the president from moving ahead with a military strike," the report said.
Pompeo also met the Holy See's diplomatic representative Paul Russell but did not talk to reporters before heading to Istanbul's airport for his flight to the Georgian capital Tbilisi.