The persecution of Christians in parts of the world is at near "genocide" levels, according to a report ordered by Foreign Secretary Jeremy Hunt.
The review, led by the Bishop of Truro the Right Reverend Philip Mounstephen, estimated that one in three people suffer from religious persecution.
Christians were the most persecuted religious group, it found.
Mr Hunt said he felt that "political correctness" had played a part in the issue not being confronted.
The interim report said the main impact of "genocidal acts against Christians is exodus" and that Christianity faced being "wiped out" from parts of the Middle East.
It warned the religion "is at risk of disappearing" in some parts of the world, pointing to figures which claimed Christians in Palestine represent less than 1.5% of the population, while in Iraq they had fallen from 1.5 million before 2003 to less than 120,000.
"Evidence shows not only the geographic spread of anti-Christian persecution, but also its increasing severity," the Bishop wrote.
Prince Charles: "It is an indescribable tragedy that Christianity is now under such threat in the Middle East''
"In some regions, the level and nature of persecution is arguably coming close to meeting the international definition of genocide, according to that adopted by the UN."
The foreign secretary commissioned the review on Boxing Day 2018 amid an outcry over the treatment of Asia Bibi, a Christian woman who faced death threats after being acquitted of blasphemy in Pakistan.
Its findings come after more than 250 people were killed and more than 500 wounded in attacks at hotels and churches in Sri Lanka on Easter Sunday.
Mr Hunt, who is on a week-long tour of Africa, said he thought governments had been "asleep" over the persecution of Christians but that this report and the attacks in Sri Lanka had "woken everyone up with an enormous shock".
He added: "I think there is a misplaced worry that it is somehow colonialist to talk about a religion that was associated with colonial powers rather than the countries that we marched into as colonisers.
'Atmosphere of political correctness'
"That has perhaps created an awkwardness in talking about this issue - the role of missionaries was always a controversial one and that has, I think, also led some people to shy away from this topic.
"What we have forgotten in that atmosphere of political correctness is actually the Christians that are being persecuted are some of the poorest people on the planet."
In response to the report, the president of the Board of Deputies of British Jews, Marie van der Zyl, said Jews had often been the targets of persecution and felt for Christians who were discriminated against on the basis of their faith.
"Whether it is in authoritarian regimes, or bigotry masked in the mistaken guise of religion, reports like the one launched today remind us that there are many places in which Christians face appalling levels of violence, abuse and harassment," she said.
The review is due to publish its final findings in the summer.
So, while everyone moans about the backlash against Muslims following Muslim terrorist attacks, a new report ordered by the UK Foreign Secretary shows that Christians are now the most persecuted religious group in the world, yet few seem willing to acknowledge this or confront the problem. My question is: what should be done about this global persecution that is nearly reaching genocide levels? The number of Christians dropped drastically in places like Palestine and Iraq. I think this needs to be talked about a hell of a lot more frequently. Most importantly, we need to recognize that Christophobia (is that a word?) is a far bigger problem than Islamaphobia.
