The British government has been slammed for refusing visas to archbishops from Iraq and Syria invited to participate in a service addressed by Prince Charles.

The three archbishops from Iraq and Syria were refused permission to enter the UK to attend the consecration of the Syriac Orthodox Cathedral of St Thomas on November 24.

Prince Charles spoke at the event and condemned the "appalling suffering" of Syria's Christians. The three clerics serve areas that have been in the front line of attacks by Islamic State.

But the Archbishop of Mosul, Nicodemus Daoud Sharaf, the Archbishop of St Matthew's in Iraq's Nineveh Plain, Timothius Mousa Shamani, and the Archbishop of Homs and Hama in Syria, Selwanos Boutros Alnemeh, were told they could not attend.

According to the Daily Express, Alnemeh was told the British Government could not offer exceptions to its policy of refusing all visa applications from Syria.

The men were also told they did not have enough money to support themselves in the UK and they might not leave.

The leader of the UK's Syriac Orthodox Christians, Archbishop Athanasius Toma Dawod, condemned the decision.

He said: "These are men who have pressing pastoral responsibilities as Christian areas held by IS are liberated.

"That is why we cannot understand why Britain is treating Christians in this way?"

A Home Office spokesman said: "All visa applications are considered on their individual merits and applicants must provide evidence to show they meet the requirements of the immigration rules."