IRAQI troops battled Isis terrorists yesterday around Mosul’s Great Mosque — where the so-called Islamic State was declared in 2014.

Federal police and the army’s rapid-response division advanced through the narrow, winding streets of the Old City, capturing the central railway station on the west side of the Old Bridge.

That left three of the city’s five crossings of the Tigris under full government control. All districts east of the river were freed earlier this year.

The government forces’ advance was supported by artillery and and air strikes.

By the afternoon, they were closing in on the 12th-century Great Mosque of al-Nuri, where Isis leader Abu Bakr al-Baghdadi reputedly declared his so-called Islamic State at Friday prayers after his followers seized the city in 2014.

West of the city, the army and Shi’ite militia completed the encirclement of the city by taking the village of Shaikh Muhammad, over the river from areas captured last week.

Iraqi and US military commanders believe that Isis leaders have already fled the city for eastern Syria and are preparing to wage a guerilla campaign after the loss of their self-declared capital in Iraq.

With their Syrian stronghold of Raqqa threatened by Kurdish militia, Isis is desperately trying to capture the government-held eastern Syrian city of Deir Ezzor, which has been under siege for almost three years now.