Footage from the frontlines of the latest battle against the Islamic State (Isis) shows Iraqi Kurdish forces as they make their first incursions into Isis territory around Mosul.

The video, captured as the Peshmerga push into Iraq's second city, the Islamic State's last major stronghold in the country, is being hosted by the partisan Kurdish news channel Rudaw.

The battle to retake Mosul from Isis (Daesh) started on Monday 17 October with the Iraqi Prime Minister Haider al-Abadi saying the offensive, which has been building for months, would be led by the Iraqi army and that national forces would be the only fighters to enter the city.

Isis has held Mosul, a city of 1.2 million inhabitants for the last two years. It was in Mosul that Abu Bakr al-Baghdadi, the leader of the militant group, declared his so-called Caliphate.

The battle to reclaim Mosul and effectively flush the terror group out from Iraq is expected to last weeks, if not months. Isis is expected to fight back using booby traps and improvised explosive devices (IEDs), CNN reported.

Isis is estimated to have between 3,500 and 5,000 fighters in Mosul, with supporters bringing the total to 7,000. The jihadists have suffered serious setbacks since January 2015, when it was at the peak of its power. Since then, it has lost 28% of the territory it once controlled, according to security and defence analysts IHS.

Mosul offensive
Kurdish Peshmerga fighters stand on top of a military vehicle as they advance towards villages surrounding Mosul Bram Janssen/ AP