Mosul- ISIS jihadists have closed the streets around Grand al-Nuri Mosque, residents of western Mosul have said, apparently in preparation for a final showdown in the battle over their last major stronghold in Iraq.

Dozens of militants were seen by residents taking up positions in the past 48 hours around the medieval mosque, the site where ISIS leader Abu Bakr al-Baghdadi declared a so-called “caliphate” in July 2014, Reuters reported on Wednesday.

ISIS’ black flag has been flying from the mosque since the militants captured Mosul and seized swathes of Iraq and Syria three years ago.

The Grand al-Nuri Mosque has become a symbolic focus of the campaign launched by Iraqi forces to recapture West Mosul.

Iraqi commanders are privately saying they hope to capture it during the month of Ramadan.

Jihadists “know that the mosque is the most important target and they are preparing for a major battle there,” said Hisham al-Hashemi, who advises several Middle East government including Iraq’s on ISIS affairs.

But a battle in or near the mosque would put the building and its famed leaning minaret at risk, experts have said.

The minaret, several feet off the perpendicular and standing on humid soil, is particularly vulnerable as it has not been renovated since 1970. Its tilt gave the landmark its popular name – al-Hadba, or the hunchback.

Over the past few days, the militants ordered dozens of families living in the Zanjili district to move into the Old City to prevent them from escaping toward the Iraqi forces trying to advance from the northern side, a resident said.

Government forces have been dropping leaflets over the districts telling families to flee but the intensity of the fighting has prevented people from escaping.

The militants have been countering the offensive with suicide car and motorbike bombs, snipers, booby-traps and mortar fire.