A militant Islamist group has demanded Christians living in the north-east of Syria pay it a tax in return for protection as it seeks to build a traditional "Caliphate" in areas it controls.
The Islamic State of Iraq and al-Sham (ISIS) published the terms under which minorities could live under its rule in a statement on the internet.
"Christians are obligated to pay Jizya tax on every adult male to the value of four golden dinars for the wealthy, half of that for middle-income citizens and half of that for the poor," their decree said. "They must not hide their status, and can pay in two instalments per year." Four dinars would amount to just over half an ounce of gold, worth £435 at current prices.
In return, Christians will not be harmed and will be allowed to worship privately, maintain their own clergy without interference and keep their own cemeteries, it added. They are implicitly allowed to continue drinking alcohol and eating pork, but may not do so publicly or trade them with Muslims. Nor may they build or renovate churches, or display the cross.
The demand carries weight because ISIS, which grew out of al-Qaeda in Iraq, has become the most feared militia in Syria. It has now been disavowed by Osama bin Laden's replacement as al-Qaeda leader, Ayman al-Zawahiri, and is effectively at war with the rest of the rebel movement, including Jabhat al-Nusra, the group seen by al-Qaeda as its representative in Syria.It controls nearly all of Raqqa province in the north-east, where it is attempting to build the institutions of an Islamic state. The decree refers to Christians as "dhimmis" - effectively protected minorities - a term that originated in the seventh century when the Muslim world was ruled by a single religious leader, the Caliph.
Raqqa, which is overwhelmingly Sunni Muslim in make-up, had a small Christian community but much if not all of it has already fled. When The Telegraph visited Raqqa city not long after forces aligned to al-Qaeda took over last year, the two alcohol shops had already been smashed up and scrawled with Islamist graffiti, along with the town's only restaurant that served alcohol.
There was said to be one Christian family still living in the town, but if so they were in hiding. Later, the crosses were removed from the top of the city's two churches.
But there is growing resentment among activists towards the stringent controls ISIS has imposed on the general population, including the wearing of the veil by women and separation of the sexes, even in bread queues. A photograph circulated of an Assad-regime flag hanging from a house, an unthinkable act of defiance until recently.
Christians used to make up around one in ten of Syria's 22 million population, but the civil war has forced an estimated 500,000 to flee their homes and villages, which are scattered across the country. Some 1,200 are thought to have been killed.
As a religious minority they enjoyed protection under President Assad, and as such have become an indirect target of the Sunni Muslim led uprising.
John Pontifex, of Aid to Church in Need, a Catholic charity that has highighted the plight of Christians in Syria, said: "We have already received reports of this nature,and if true, they spell out loud and clear the degree to which Christians are under attack and at risk.
"There seems to be a desire to flush Chrisians out or reduce them to second class status."
Imposition of the so-called "dhimmi" rules conforms precisely with regime claims that the rebels are seeking to take Syria back to the Middle Ages.
Aymenn al-Tamimi, an Oxford University-based academic expert on Iraq and Syrian jihadists, said the imposition of the jizya was derived from a verse in the Quran, which demanded submission by the "people of the Book" - Jews and Christians - who did not follow Islam.
In a post to the Syria Comment website, he added: "In case ISIS's ambitions to a global caliphate were still not apparent to anyone, ISIS's official Twitter account for Raqqa province had this to say on the imposition of the dhimmi pact: 'Today in Raqqa and tomorrow in Rome.'"