When members of Father Martin Hermis Dawood’s congregation used to ask guidance about fleeing Iraq, his advice was to be strong.

Iraq’s Christians had to stay together and hope, he would counsel, no matter how bleak the situation may look in a country stricken by sectarian violence and terrorism.

Yet the dramatic arrival two years ago of Islamic State extremists forced him to change his guidance. Now he tells his flock that if they want to leave, they should go immediately.

“I tell them one thing. If you are thinking about leaving, go now, do not wait,” the 41-year-old Assyrian priest told the Telegraph.

For many in Iraq’s ancient and beleaguered churches, the rise of the extremist Islamic State in Iraq and Levant (Isil) and its seizure of territory where Christians have worshipped for two millennia, has ended years of equivocation.