NAJAF, IRAQ (REUTERS) - Pope Francis entered a narrow alleyway in Iraq's holy city of Najaf to hold a historic meeting with the county's top Shi'ite cleric and visited the birthplace of the Prophet Abraham on Saturday (March 6) to condemn violence in the name of God as "the greatest blasphemy".

The back-to-back inter-religious events some 200 km apart, one in a dusty, built-up city and the other in a desert plain, reinforced the main theme of his risky trip to Iraq - that the country has suffered far too much.

"From this place, where faith was born, from the land of our father Abraham, let us affirm that God is merciful and that the greatest blasphemy is to profane his name by hating our brothers and sisters," Francis said in Ur, where Abraham was born.

The Pope's meeting in the holy southern city of Najaf, during a whirlwind and risky tour of Iraq, marked the first time a pope has met with such a senior Shi'ite cleric.

Children lined a street and waved Iraqi and Vatican flags at the leader of the world's Catholics.

The Pontiff has visited predominantly Muslim countries, including Turkey, Jordan, Egypt, Bangladesh, Azerbaijan, the United Arab Emirates and the Palestinian territories, using those trips to call for inter-religious dialogue.

After his 55-minute meeting with Grand Ayatollah Sistani, Pope Francis headed to the ruins of ancient Ur in southern Iraq, revered as the birthplace of Abraham, father of Judaism, Christianity and Islam.

After the meeting, Sistani, one of the most important figures in Shi'ite Islam, called on world religious leaders to hold great powers to account and for wisdom and sense to prevail over war.

The pope also called for religious communities to work together.

"(He) underlined the importance of collaboration and friendship between religious communities so that, by cultivating mutual respect and dialogue, we can contribute to the good of Iraq, of the region," the Vatican said in a statement after the meeting, which lasted about 45 minutes.

Pope Francis is scheduled to give a speech at an interreligious meeting. After flying back to Baghdad, he is expected to deliver mass at the Chaldean Cathedral of Saint Joseph.

Grand Ayatollah Sistani is one of the most important figures in Shi'ite Islam, both within Iraq and beyond. He wields enormous influence over politics.

His edicts sent Iraqis to free polls for the first time in 2005, rallied hundreds of thousands of men to fight Islamic State in 2014 and toppled an Iraqi government under pressure from mass demonstrations in 2019.

The 90-year-old rarely takes meetings, and has refused talks with Iraq's current and former prime ministers, according to officials close to him.

Grand Ayatollah Sistani agreed to meet the Pope on condition that no Iraqi officials would be present, said a source in the president's office.

The meeting with Pope Francis took place at Grand Ayatollah Sistani's humble home which he has rented for decades, located in a narrow alleyway in Najaf.

An ascetic cleric of almost mythical stature among millions of Shi'ite followers, Grand Ayatollah Sistani intervened at critical junctures as Iraq lurched from one crisis to another.

A gaunt figure, the reclusive cleric works from his spartan base near the golden-domed Imam Ali shrine in Najaf. He is rarely seen in public.

Pope Francis began his most risky foreign trip on Friday, flying into Iraq amid the tightest security ever seen for a papal visit to appeal to the country's leaders and people to end militant violence and religious strife.

The country has deployed thousands of security personnel to protect him during the visit, which comes after a spate of rocket and suicide bomb attacks and a spike in Covid-19 cases.

Pope Francis said he was making the trip to show solidarity with Iraq's devastated Christian community of around 300,000, just one fifth of the number before the US invasion in 2003 and the brutal Islamist militant violence that followed.

Pope John Paul II came close to visiting, but had to cancel a planned trip in 2000 after talks with the government of then-leader Saddam Hussein broke down.

The 84-year-old Pope Francis, limping from what appears to be a fresh flare-up of his painful sciatica, made an impassioned call for Iraqis to finally give peacemakers a chance during a gathering of Iraqi officials and diplomats at the presidential palace.

He later paid tribute to people killed in attacks motivated by religion, visiting a Baghdad church where Islamist gunmen killed about 50 worshippers in 2010.

Iraq's security has improved since the defeat of the Islamic State in Iraq and Syria in 2017, but the country continues to be a theatre for global and regional score-settling, especially a bitter US-Iran rivalry that has played out on Iraqi soil.

The US invasion of 2003, after years of international sanctions and a devastating war with Iran instigated by former leader Saddam Hussein in the 1980s, plunged Iraq into sectarian conflict and chronic mismanagement that has plagued it since.