Dozens of Muslims demonstrated on Wednesday inside a historic church against Pope Benedict XVI's planned visit here next week as an Islamist party called for a large weekend rally to show the pontiff was 'unwelcome' in Turkey.
Shortly before the unrest at the 6th century Byzantine Hagia Sophia Church, an Istanbul landmark, the Turkish government said it hoped the visit will help bridge the divide between East and West.
Riot police detained about 40 protesting members of a nationalist-Islamist group who entered the edifice -- now a museum -- as regular visitors, then gathered to chant slogans against the visit and hold evening prayers before being evicted, eyewitnesses said.
The Vatican late on Wednesday said the demonstration was not of particular concern.
"I consider these to be occasional and limited incidents and that do not call into question the substance or the atmosphere surrounding the (pope's) visit which we expect to take place in a calm atmosphere," the Vatican's press chief, Father Federico Lombardi said, according to the ANSA news agency.
"The situation does not raise any particular concerns even though it is unpleasant," he added.
The church is one the venues Benedict XVI is scheduled to visit during his four-day trip to Turkey, which starts on Tuesday in Ankara.
It was converted into a mosque when the Ottomans conquered the city, then called Constantinople, in 1453, and transformed into a museum in the 1930s.
Benedict's visit, his first to a Muslim country, follows uproar across the Muslim world over remarks he made in September linking Islam and violence.
His comments also provoked fury in Turkey, a 99-percent Muslim but strictly secular country bidding to join the European Union, which criticised them as a blow to efforts to reconcile religions.
The Islamist Felicity Party (SP) called for a large demonstration on Sunday under the slogan, "The sly and ignorant pope is not welcome," and said that one million people were expected to attend.
"We have infinite respect for all religions and their representatives, but we cannot remain silent in the face of declarations that go against our faith," Osman Yumakogullari, a senior SP official, said.
"In September, Pope Benedict XVI insulted the (revered) Prophet Mohammed (PBUH) who, according to him, brought inhumane and satanic things to the world," he said.
The SP, an Islamist party, is an offshoot of the Welfare Party, ousted from power in 1997 and outlawed the following year for threatening Turkey's secular system.
The party's moderate members, among them Prime Minister Recep Tayyip Erdogan, left the movement and now form the core of the ruling Justice and Development Party, which has disowned its Islamist roots and describes itself as a "conservative democratic" movement respectful of secularism.
In Ankara, the government sought to convey a message of reconciliation.
"The pope's visit is very important for Turkey... We are going to do everything in our hands for the visit to be successful," foreign ministry spokesman Namik Tan told reporters.
Turkey hopes the visit "will constitute a very important message to clear some misunderstandings between East and West and to spread understanding of reconciliation and alliance between civilisations," he said.
The country's chief Muslim cleric said the visit would encourage dialogue, but insisted it would not heal the offence caused to Muslims by the pope's "prejudiced and aggressive" comments.
"The visit is a positive step to open the door for dialogue... We must keep this door open," Ali Bardakoglu told NTV television.
"But it will not resolve everything," he said. "Healing wounds can become possible only if those who inflict them continue to act carefully over time."
He called on Turks to avoid violence at demonstrations.
"We do not have to share the views of our guest, but we are obliged to show him hospitality," he said. "I advise citizens to be calm and prudent."
After talks with officials in Ankara, the pope is expected to visit a monastery at the site where the Virgin Mary is believed to have spent the last years of her life in the ancient city of Ephesus, near the western city of Izmir.
He will then go to Istanbul to meet Patriarch Bartholomew I, the spiritual leader of the world's 250 million Orthodox believers.