David Cameron has delivered his most explicitly Christian Christmas message yet, stating that Britain is a "Christian country" that must remember what the birth of Christ represents. 

In his Christmas message the Prime Minister said: "As a Christian country, we must remember what his birth represents: peace, mercy, goodwill and, above all, hope."

It is because of the nation's Christian heritage that it has been so tolerant to non-Christians, he added.

"I believe that we should also reflect on the fact that it is because of these important religious roots and Christian values that Britain has been such a successful home to people of all faiths and none."

He also spoke about the traumas suffered by the millions of displaced people around the world, particularly in the Middle East, after a year of unprecedented horrors perpetrated by Daesh, or Islamic State. 

"If there is one thing people want at Christmas, it's the security of having their family around them and a home that is safe. But not everyone has that. Millions of families are spending this winter in refugee camps or makeshift shelters across Syria and the Middle East, driven from their homes by Daesh and Assad."

Christians from Africa to Asia will go to church on Christmas morning full of joy, but many will be there in fear of persecution as well.

And nor was everyone in Britain in a good place to celebrate or enjoy the festival.

"Throughout the United Kingdom, some will spend the festive period ill, homeless or alone."

He paid special tribute to the thousands of doctors, nurses, carers and volunteers who are giving up their Christmas to help the vulnerable.

According to Crisis, the charity for the single homeless which has opened its doors to 4,000 people over the break, one in four people in Britain this Christmas will spend the holiday alone. 

Cameron said: "Right now, our brave armed forces are doing their duty, around the world: in the skies of Iraq and Syria, targeting the terrorists that threaten those countries and our security at home; on the seas of the Mediterranean, saving those who attempt the perilous crossing to Europe; and on the ground, helping to bring stability to countries from Afghanistan to South Sudan.

"It is because they face danger that we have peace. And that is what we mark today as we celebrate the birth of God's only son, Jesus Christ – the Prince of Peace." 

The message was criticised by the National Secular Society, who recently joined forces with Christian groups in a campaign to protect freedom of speech.  

Campaigns manager Stephen Evans said it was "disappointing" to see Cameron once again speak of Britain being a Christian country.

"Christianity is just one influence among many that shape our ways of life, and Mr Cameron would do well to remember that we also have Enlightenment values and secularism to thank for the freedoms we enjoy today. David Cameron needs to appreciate that he isn't a leader of Christians, he's the Prime Minister of a diverse, multi-faith, increasingly non-religious nation. We look to political leaders for leadership, not theology, and this kind of language reveals him to be less than statesmanlike."