Pope Francis on Friday called for dialogue between faiths to end the Islamist extremism plaguing the Middle East as he visited Turkey on his first trip to the overwhelmingly Muslim but officially secular state.

Turkish President Recep Tayyip Erdogan, who welcomed Pope Francis as the first foreign dignitary to his controversial new presidential palace outside Ankara, for his part issued a strong warning about rising Islamophobia in the world.

Turkish President Recep Tayyip Erdogan savaged critics of his remarks that Muslim explorers traveled to the Americas before Columbus as suffering from an "ego complex", reaffirming his belief their purported feat was an historical fact.

"I have been the target of heavy criticism by the Western media," Erdogan said during an address at a meeting of Standing Committee for Economic and Commercial Cooperation of the Organisation of Islamic Cooperation (COMCEC) in Istanbul.

Turkish authorities said on Wednesday they intend to go ahead with the redevelopment of Istanbul's Gezi Park, the same project that sparked deadly nationwide anti-government protests last year.

The controversial plans to raze the park and rebuild an Ottoman-era army barracks on the site, which is adjacent to the main Taksim Square, have been included in the Istanbul municipality's strategic agenda for 2015-2016.

Turkish President Recep Tayyip Erdogan on Wednesday expressed frustration that the U.S. and its allies were not responding to conditions set for his country to play a greater role in the coalition against militants in Syria.

His complaint came as a U.S. special presidential envoy, John Allen, visited Ankara for previously unannounced talks with Turkish officials.

Turkey could scrap a controversial plan to buy missile defense systems from China that alarmed the United States and its Western allies, Turkish and European sources said Wednesday.

Key NATO member Turkey said in September last year it was entering negotiations with the China Precision Machinery Export-Import Corporation (CPMIEC) to acquire its first long-range anti-missile systems.

Turkey needs to develop a strategy to counter pressure to acknowledge the World War I killings of Armenians as a genocide as the 100th anniversary of the massacres looms, a top Turkish diplomat said Monday.

Altay Cengizer, director general for policy planning at the Turkish foreign ministry, told the Hurriyet daily that U.S.-based Armenian diaspora groups saw the centenary as an opportunity to prove that genocide was carried out and planned by the Ottoman authorities.

For critics, it is the latest excess of an authoritarian ruler, a folly comparable to the notorious Palace of the People of deposed Romanian dictator Nicolae Ceausescu.

Even the Turkish deputy prime minister admits the costs ran a little high.

Turkey is pursuing a delicate but potentially dangerous strategy over the besieged Syrian town of Kobane, working to thwart Kurdish domination of northern Syria but also running the risk of a breakdown of its peace process with the Kurds.

While the United States and the West see the Islamic State jihadists battling Kurds for Kobane as enemy number one, Turkey is equally worried about the risks to its security from separatist Kurdish groups.

President Recep Tayyip Erdogan's grandiose new presidential palace is costing Turkey more than $600 million, nearly twice previous estimates, the country's finance minister said Tuesday.

The vast new 1,000-room palace -- more than 30 times larger than the White House and bigger even than France's sprawling Palace of Versailles -- has been condemned by the opposition as an absurd extravagance that showed Erdogan was slipping towards authoritarian rule.

An Istanbul court on Monday opened the retrial of more than 200 military officials accused of plotting against Turkey's Islamic-rooted government, after a top court in June quashed their original convictions.

A total of 236 defendants, including a number of high-ranking retired generals, were to appear before the court to testify on charges of seeking to bring down the government of now President, then prime minister, Recep Tayyip Erdogan in 2003.