Pope Francis prepared to visit conflict-stricken Iraq

The Pope has said he is willing to visit scenes of the conflict in Iraq as he criticised the "unjust aggression" of Islamic extremists who have forced religious minorities to flee from Iraq.

"In these cases, where there is an unjust aggression I can only say that it is legitimate to stop the unjust aggressor," Pope Francis said of the Islamic State of Iraq and the Levant, known as Isis.

Speaking to journalists onboard a flight to Rome from South Korea at the end of a five-day visit, the Pope said: "I stress the verb 'to stop'. I am not saying 'bomb' or 'make war', but stop him [the aggressor]. The means by which he can be stopped must be evaluated."

Vincenzo Pinto | AFP | Getty Images

The 77-year old pontiff said he would be willing to travel to visit persecuted Christian minorities in the area "if necessary . . . if it is a possibility I would be available . . . in this moment it is not the best thing but I am available," he said.

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The Pope's comments on the conflict have strengthened in tone since the start of August, when the Vatican communicated the Pope's "prayerful concern" over the violence in Iraq towards "defenceless populations" as Christian communities fled from their villages.

He urged the UN to accelerate efforts to quell the conflict, stressing that it could not be stopped by "one single nation", adding that the UN was created for this purpose after second world war.

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The Pope said he had recently written to Ban Ki-moon, the General Secretary of the UN, and had also decided to send a "personal envoy" to the region, Cardinal Filoni.

He also spoke of his deep sadness about the killing of children in war zones, appearing also to refer to the recent conflict in Gaza.

"We must [stop and] think about the level of cruelty to which [the world] has arrived. the level of human cruelty right now is a little frightening," he said.

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The Pope has been urging his 4.37m followers on Twitter to pray for peace in the region. Before boarding his flight to Rome, he tweeted: "So many innocent people have been driven from their homes in Iraq. Lord, we pray they may go back soon."

Earlier in the week, he had tweeted: "My heart bleeds especially when I think of the children in Iraq. May Mary, Our Mother, protect them."

During the question and answer session with reporters, the Pope also confirmed that he plans to visit the UN headquarters in New York when he visits the US next year.

He also said that President Obama had invited him to address US Congress in Washington, and that he hoped to combine both visits with a trip to Philadelphia to attend the Catholic Church's World Meeting of Families.