At first sight, Donald Trump appeared to make a major concession to Christians in the Middle East last month when he said that he would give priority to Christians when it comes to applying for refugee status in the US.

In an interview with the Christian Broadcasting Network, the new President said: 'We are going to help them [Christians]. They've been horribly treated. Do you know if you were a Christian in Syria it was impossible, at least very tough to get into the United States? If you were a Muslim you could come in, but if you were a Christian, it was almost impossible and the reason that was so unfair, everybody was persecuted in all fairness, but they were chopping off the heads of everybody but more so the Christians. And I thought it was very, very unfair.'

Yet according to some Christian leaders in the troubled region, giving Christians priority will both inflame tensions with other religions and groups and also encourage even more Christians to leave the region of their origin.

After all, Christians are under threat from all sides in the Middle East. Tens of thousands of Christians were driven from their homes in Iraq by the ISIS advance in the summer of 2014. Some 80,000 Christian refugees fled Mosul and the Nineveh Plain under threat of forced conversion or execution but remain inside Iraq in the Kurdish capital of Irbil. Elsewhere, Christians are fleeing the literal birthplace of Jesus himself, as Israeli settlements and the 'security barrier' or 'wall' close in around Bethlehem. Aleppo and Syria more broadly have been ravaged by civil war.

Patriarch Louis Sako of the Chaldean Catholic Church in Baghdad recently called the provision 'a trap for Christians in the Middle East'. He said: 'Every reception policy that discriminates for the persecuted and suffering on religious grounds ultimately harms the Christians of the East, because among other things [it] provides arguments to all propaganda and prejudice that attack native Christian communities of the Middle East as 'foreign bodies,' supported and defended by Western powers.'

Backing this view, the Chaldean Bishop of Aleppo, Antoine Audo, said that any policy appearing to prefer Christians over Muslims 'feeds fanaticism and extremism'.

Not all Christian leaders agree, however. Archbishop Bashar Warda of Erbil in Iraq told Crux: 'As long as this is understood as something available to all the minority communities of Iraq, and not just to the Christians, I do not think this will make it harder for us Christians here in Iraq.'

Which brings us to an important distinction, not apparently made by Trump himself, between a policy that is giving overt preference only to Christians, and one that contains a fast-track provision for all victims of ISIS, which would include, for example, Yazidis, and in some cases Shi'a Muslims.

But a range of Christian leaders in the US and UK have anyway criticised the executive order which is known as a 'Muslim ban'. They say that discrimination against any faith group violates principles of religious freedom.

However, there remains the crucial moral question of whether the UK and the US should be encouraging the Middle East to be emptied of Christians.

Habib Ephrem, the secretary general of the Gathering of Christians in the Middle East, said bluntly: 'We want don't priority visas. We don't want him to take us.' He told Time: 'That's the wrong message and the wrong policy...ISIS expels people from their homeland and then you take them to the West. So what? You are doing the policy of ISIS?'

And Chawkat Moucarry, World Vision's director for interfaith relations, told Christianity Today: 'This policy will encourage Christians to migrate, which is exactly what Christian leaders in Syria are fighting against. It is important for Christians to live in Muslim countries. Because through them, Muslims will learn to accept the other. We must learn this principle in order to have a democratic society. Extremists say there is only one way to think or believe. So keeping Christians in the area is an indirect way to counter extremism and learn that diversity is good.'