Iraqi Christians persecuted by ISIS are losing hope for their future, two years since militants overran Mosul and the Nineveh Plain, forcing hundreds of thousands to flee.

"I see no future for us [here]", Raad Bahnam Samaan told the Associated Press. He fled Qaraqosh – once home to Iraq's largest Christian population – in August 2014 along with his wife and five children. They now live in an IDP camp on the outskirts of Erbil.

Of returning home, he said: "There is always hope, but when? Nobody knows. It might be a year, two years, a day, a couple of days. Three or four years from now if we go home there won't be anything left of our house."

Samaan worries especially for his children. "The boys are growing up," he said. "How can I secure their future?"

Even if ISIS is defeated, he warned that Iraq may not be safe for Christians and other religious minorities. The insurgency has bred distrust between communities, Samaan said, and he is concerned that even once the militants are gone, the atmosphere of fear will remain.

"We'll still be afraid," he said. "I will go to Mosul and I will be afraid because they will say, 'Here comes the Christian'."

Before the US invasion in 2003, there were around 1.5 million Christians living in Iraq. There are now thought to be fewer than 300,000.

Many have fled overseas, but tens of thousands are living in refugee camps within Iraq. ISIS has destroyed numerous ancient Assyrian Christian sites, artifacts and temples in what is seen as an attempt to 'cleanse' the coutry of its Christian heritage.

On Sunday, the second anniversary of the exodus from the Nineveh Plain, the European Syriac Union released a statement calling for immediate action and condemning the "massive genocidal destruction of Chaldean-Syriac-Assyrian people and their millennial cultural, historical and religious heritage by demolishing churches, monasteries and historical sites".

"There is historical and moral responsibility for Iraq, regional and international community and institutions namely United Nations to stand with the vulnerable groups, recognise genocides against them and support them by accelerating the liberation of Nineveh Plain and supporting safe zone, autonomy in the region which will open the way to self administration," the statement said.

"In these turbulent times, Chaldean-Syriac-Assyrian people dispersed in different regions should stand with their brethren in the homeland in Iraq and Syria and raise their voices for the existential demands on the historical homeland of Bethnahrin."