Isis has launched an “extremely defensive” propaganda effort to defend its slaughter of women and children as it struggles to retain territory, troops and attention.

The latest edition of the terrorist group’s Rumiyah magazine celebrated bombings that killed at least 45 people marking Palm Sunday at Coptic churches in Egypt.

Hundreds of people attended the victims’ funerals, with Egyptians of all religions uniting to condemn the bloodshed and the government threatening a new crackdown.

Jean-Marc Rickli, a research fellow at King’s College London and the Geneva Centre for Security Policy, said that even for some of Isis’s supporters attacks on churches in the Arab world is “crossing a red line”.

“Isis is really seeking to justify its actions, not only in the Middle East but also in the West and Asia. It’s very defensive,” he told The Independent.

“They’ve got a double challenge – as well as Isis is losing position, al-Qaeda is reinforcing theirs – especially in Syria.

“They still have to maintain momentum to attract new candidates but also they have to justify that what they’re doing, which is contrary to what most people would think is right.”

Opponents of Isis, including rival terrorist groups, have cited its killing of women and children – particularly Muslims – in indiscriminate terror attacks as proof of their takfir (disbelief).

Mourners pray next to coffins of victims of the blast at the Coptic Christian Saint Mark's church in Alexandria during a funeral procession at the Monastery of Marmina in the city of Borg El-Arab (Getty) (Getty Images)

Christians are also afforded protection under sharia as protected “dhimma”, and were required to pay a special tax under caliphates in the Islamic Golden Age.

In an “interview” in Rumiyah, the leader of Isis’s faction in Egypt admitted that the “prevailing trend in many people’s reactions is that of denunciation, as well as disassociation ... and of offering condolences”.

But in a lengthy propaganda article, Isis sought to justify its actions by claiming that “belligerent” Christians in Egypt deserve no protection.

It said it was “permissible” to murder all men and take women, children, the elderly and ill as slaves.

“With regards to those of the non-combatant women and children from among the belligerent Christians who are killed unintentionally, their blood is waste,” the article continued.

It claimed that the murder of women and children in indiscriminate terror attacks or bombardment was also allowed, citing Mohamed’s use of catapults in a medieval city siege.

Isis also attempted to justify its own use of children as suicide bombers and child soldiers, having set up military training camps and even a jihadi alphabet app to start indoctrination as early as possible.

Parents escaping the group’s rule have told of their efforts to resist Isis’s bloody curriculum, which includes watching gory propaganda videos and bomb-making, and the group is now targeting mothers specifically with its propaganda.

Suspected child suicide bomber stripped of explosives belt in Iraq

An article in Rumiyah said “righteous offspring will to bring forth from us a generation that will wage jihad”, ordering women to live in its territories to “painstakingly endeavour” to use their children for the terrorist group’s benefit.

“Every woman to whom Allah has granted the blessing of giving birth in the Islamic State should take advantage of this tremendous grace,” it said.

“They [should] grow up with their eyes becoming accustomed to seeing weapons and equipment, including rifles, tactical vests, bullets, grenades, and explosive belts.”

Isis encouraged women to force their children to watch and read its propaganda to “nurture the love of jihad and hatred towards their enemies”.

The group conceded that mothers “may hear criticism from some people” but claimed there would be heavenly reward.

The propaganda magazine, which is published in many languages, also ordered foreign women to ensure their children learn Arabic “correct and free of linguistic errors”.

Isis has increasingly used child fighters and suicide bombers to defend its waning territory in Syria and Iraq – most prolifically in the ongoing battle for Mosul, where thousands of militants have been killed.

A lengthy speech by the group’s official spokesman, Abul-Hasan Al-Muhajir, acknowledged losses and told soldiers not to “weaken”, while making a fresh pitch for new recruits.

After years of sustained condemnation for other terrorist groups, he claimed that Isis has “not closed its doors” on defectors from elsewhere.

In pictures: Mosul offensive Show all 40 1 /40 In pictures: Mosul offensive In pictures: Mosul offensive A doctor carries an Iraqi newborn baby at a hospital in Mosul, Iraq July 18, 2017. Reuters In pictures: Mosul offensive Iraqi girls play at a yard of a school in Mosul, Iraq July 18, 2017alal Reuters In pictures: Mosul offensive A woman on crutches who is a relative of men accused of being Islamic State militants is seen at a camp in Bartella, east of Mosul, Iraq July 15, 2017. Picture taken July 15, 2017. Reuters In pictures: Mosul offensive A displaced girl, who fled from home carries a doll at Hamam al-Alil camp south of Mosul, Iraq July 13, 2017. Reuters In pictures: Mosul offensive Iraqi federal police members and civilians celebrate in the Old City of Mosul on 9 July 2017 after the government's announcement of the "liberation" of the embattled city. Iraqi Prime Minister Haider al-Abadi's office said he was in "liberated" Mosul to congratulate "the heroic fighters and the Iraqi people on the achievement of the major victory" AFP/Getty Images In pictures: Mosul offensive A picture taken on 9 July 2017, shows a general view of the destruction in Mosul's Old City. Iraq will announce imminently a final victory in the nearly nine-month offensive to retake Mosul from jihadists, a US general said Saturday, as celebrations broke out among police forces in the city. AFP In pictures: Mosul offensive Members of the Iraqi federal police raise the victory gesture as they ride on a humvee while advancing through the Old City of Mosul on 28 June 2017, as the offensive continues to retake the last district held by Islamic State (IS) group fighters. AFP/Getty Images In pictures: Mosul offensive Smoke billows as Iraqi forces advance through the Old City of Mosul on 26 June 2017, during the ongoing offensive to retake the last district held by the Islamic State (IS) group. AFP/Getty Images In pictures: Mosul offensive An Iraqi man wearing the green scarf of the Shi'ite faith kisses an Iraqi Army soldier on safely reaching the Iraqi forces position as Iraqi civilians flee the Old City of west Mosul where heavy fighting continues on 23 June 2017. Iraqi forces continue to encounter stiff resistance with improvised explosive devices, car bombs, heavy mortar fire and snipers hampering their advance. Getty Images In pictures: Mosul offensive A picture taken from the inside of an Iraqi forces armoured vehicle shows residents walking through a damaged street as troops advance towards Mosul's Old City on 18 June 2017, during the ongoing offensive to retake the last district still held by the Islamic State (IS) group. Military commanders told AFP the assault had begun at dawn after overnight air strikes by the US-led coalition backing Iraqi forces. They said the jihadists were putting up fierce resistance. AFP/Getty Images In pictures: Mosul offensive Iraqi Army soldiers advance in a destroyed street after an Iraqi forces airstrike targeted an Islamic State sniper position 17 June 2017 in al-Shifa, the last district of west Mosul under Islamic State control. IS snipers, as well as car and suicide bomb attacks continue to hinder the Iraqi forces efforts to retake the final district. A series of airstrikes by Iraqi helicopter gunships attempted to hit multiple Islamic State sniper positions in al-Shifa. Getty Images In pictures: Mosul offensive An Iraqi soldier frisks a displaced Iraqi man at a temporary camp in the compound of the closed Nineveh International Hotel in Mosul on 16 June 2017 which was recovered by Iraqi troops from Islamic State group fighters earlier in the year. A screening centre set up in the compound's fairgrounds sees a constant stream of Iraqis fleeing the battle for Mosul, awaiting their turn to be checked by the Iraqi forces who are searching for suspected Islamic State (IS) group members. The small fairground lies at the end of a pontoon bridge across the Tigris recently opened to civilians that is the only physical link between the two banks of the river. AFP/Getty Images In pictures: Mosul offensive Iraqis staying at the al-Khazir camp swim in a river near the camp for internally displaced people, located between Arbil and Mosul on 11 June 2017. AFP/Getty Images In pictures: Mosul offensive Iraqi government forces drive on a road leading to Tal Afar on 9 June 2017, during ongoing battles to retake the city from Islamic State (IS) group fighters. AFP/Getty Images In pictures: Mosul offensive An Iraqi policeman carries a poster bearing an image of Mosul's iconic leaning minaret, known as the "Hadba" (Hunchback), on 22 June 2017. AFP/Getty Images In pictures: Mosul offensive Iraqis stand in line to receive food aid in western Mosul's Zanjili neighbourhood on 7 June 2017, during ongoing battles as Iraqi forces try to retake the city from Islamic State (IS) group fighters. Living conditions in Mosul have again deteriorated since the start of the Iraqi government's offensive on the city in October in which they retook a large part of the west of the city. AFP/Getty Images In pictures: Mosul offensive Displaced Iraqis carry lightbulbs and sacks as they evacuate from western Mosul's Zanjili neighbourhood as government forces advance in the area during their ongoing battle against Islamic State (IS) group fighters on 13 May 2017 AFP/Getty Images In pictures: Mosul offensive A member of the Iraqi Counter-Terrorism Service (CTS) flashes the victory gesture as he patrols in western Mosul's al-Islah al-Zaraye neighbourhood on 13 May 2017 AFP/Getty Images In pictures: Mosul offensive Iraqi army soldiers from the 9th armoured division on a truck flash the sign of victory as they drive back from Mosul to the town of Qaraqosh (also known as Hamdaniya) Getty In pictures: Mosul offensive Members of Iraqi forces flash the sign of victory on their vehicle as they advance towards Hammam al-Alil area south of Mosul Getty In pictures: Mosul offensive A member of Iraqi security forces gestures in Hammam al-Alil, south of Mosul, Iraq Reuters In pictures: Mosul offensive Iraqi children, one flashing the sign of victory, greet Iraqi army's soldiers from the 9th armoured division in the area of Ali Rash, adjacent to the eastern Al-Intissar neighbourhood of Mosul Getty In pictures: Mosul offensive Peshmerga forces look at a tunnel used by Islamic State militants near the town of Bashiqa, east of Mosul, during an operation to attack Islamic State militants in Mosul, Iraq Reuters In pictures: Mosul offensive An Iraqi soldier takes a photograph with his phone as his comrade stands next to a detained man, whom the Iraqi army soldiers accused of being an Islamic State fighter, who was fleeing with his family in the Intisar disrict of eastern Mosul, Iraq Reuters In pictures: Mosul offensive Iranian Kurdish female members of the Freedom Party of Kurdistan (PAK) hold a position in an area near the town of Bashiqa, some 25 kilometres north east of Mosul Getty In pictures: Mosul offensive Iraqi families, who fled their homes in Hamam al-Alil, gather on the outskirts of their town Getty In pictures: Mosul offensive Displaced people walk past a checkpoint near Qayara, south of Mosul, Iraq AP In pictures: Mosul offensive Iraqi families who were displaced by the ongoing operation by Iraqi forces against jihadists of the Islamic State group to retake the city of Mosul, are seen gathering in an area near Qayyarah In pictures: Mosul offensive A boy who just fled Abu Jarbuah village is seen with his family at a Kurdish Peshmerga position between two front lines near Bashiqa, east of Mosul, Iraq Reuters In pictures: Mosul offensive An Iraqi child eats a pomegranate upon the arrival of Iraqi forces in the village of Umm Mahahir, south of Mosul Getty In pictures: Mosul offensive People who just fled Abu Jarbuah village sit as they eat at a Kurdish Peshmerga position between two front lines near Bashiqa, east of Mosul, Iraq Reuters In pictures: Mosul offensive A couple who just fled Abu Jarbuah village are escorted by Kurdish Peshmerga soldiers Reuters In pictures: Mosul offensive Women carry a boy over a wall as civilians flee their houses in the village of Tob Zawa, Iraq AP In pictures: Mosul offensive An Iraqi soldier and a civilian ride a motorbike as smoke rises behind them, on the road between Qayyarah and Mosul Getty In pictures: Mosul offensive A member of Iraqi forces, wearing a skull mask, waits at a checkpoint for people fleeing the main hub city of Mosul Getty In pictures: Mosul offensive An Iraqi soldier sits at a checkpoint in an area near Qayyarah Getty In pictures: Mosul offensive Iraqi men prepare food portions for Iraqi forces deployed in areas south of Mosul Getty In pictures: Mosul offensive Iraqi forces celebrate upon the arrival of vehicles bringing food to them Getty In pictures: Mosul offensive Iraqi childen smoke cigarettes upon the arrival of Iraqi forces in the village of Umm Mahahir, south of Mosul Getty In pictures: Mosul offensive A member of Iraqi forces distributes drinks to children in the village of Umm Mahahir, south of Mosul Getty

“There has always been tremendous competition for jihadis,” Dr Rickli said.

“In 2014 you had this constant flow of newcomers in Syria and Iraq and that’s no longer the case, and on top of that they are being attacked by the anti-Isis coalition and suffering lots of casualties.”

Al-Qaeda, which operates in Syria through the Islamist alliance Hayat Tahrir al-Sham, has vocally opposed Isis and used the global focus on its former subsidiary to expand its own territory.

Ayman al-Zawahiri, who succeeded Osama bin Laden when he was killed in 2011, has criticised Isis for killing and “slandering” his own jihadis and urged the “ones who seek the truth” to join al-Qaeda instead.

An audio message released earlier this year accused Isis of "madness and lies", more than a decade after he personally wrote to the group’s leader opposing his militants’ indiscriminate suicide bombings, targeting of Shia Muslims and hostage executions.

Isis has increasingly turned to terror attacks as a way of gaining momentum – and attention – as its territory shrinks and issued a new series of detailed guidelines for atrocities in the West.

As well as instructions on how to carry out lorry attacks, illustrated with photos including a gay pride parade and Piccadilly Circus, Rumiyah detailed new strategies of attack while praising “martyrs” including Westminster attacker Khalid Masood.

Grim new suggestions for followers included creating a fake job advert, advertising a property for rent or selling second-hand items online as a means of rounding up and slaughtering “disbelievers”.