David Cameron has been urged to raise religious freedom with Egyptian president Abdel Fattah El-Sisi during his official visit to the UK this week.

Protests greeted Sisi's arrival in the UK yesterday. He has been accused of crimes against humanity and Christian Solidarity Worldwide (CSW), a religious freedom charity, has written to the prime minister to ask him to raise "long-term issues" surrounding freedom of religion or belief.

Terrorism is on the increase in Egypt as ISIS-affiliated groups target government buildings, and the battle against terrorism has meant that fundamental rights such as the freedom of religion and belief are increasingly curtailed, said CSW in a statement.

In addition to these short-term concerns, CSW also raised more enduring issues of religious persecution.

"There are persistent concerns regarding full enjoyment of freedom of religion or belief," the statement read.

After former president Mohamed Morsi was ousted in a military coup in July 2013, Christians were blamed for orchestrating the removal and a "wave of sectarian violence targeting Christians" rose across Egypt. Since then, "problems persist" for Christians, CSW said.

The Coptic community in north Egypt are frequently subject to kidnapping, harassment and the destruction of churches. There is also a "worrying trend" of charges for blasphemy or insulting religion made against minority faith groups, which in the main part involve Christians, the statement added.

"The alarming increase in terrorism understandably necessitates extraordinary measures," said Christian Solidarity Worldwide.

"However, we urge the Prime Minister to use the opportunity of President Sisi's first visit to the UK to encourage the formulation of a counter-insurgency policy that is tolerant of civil society and of the peaceful expressions of dissent that are vital for the emergence of a healthy pluralistic society."

He added: "It is important that the continuing difficulties experienced by non-majority religious communities, including the harassment of Coptic communities in Upper Egypt and the proliferation of religious defamation charges, are also addressed during these discussions.

"The Egyptian constitution proclaims that 'Freedom of Belief is absolute'; however, religion-related violations and discrimination prevent the enjoyment of freedom of religion or belief by every faith community, which in turn mitigates against the emergence of a just and prosperous society."