Iraqi forces launch a rocket in Mosul's eastern Al-Intisar neighbourhood on December 30, 2016, during an ongoing military operation against Islamic State (IS) group jihadists (AFP Photo/AHMAD AL-RUBAYE)

Mosul (Iraq) (AFP) - Two elite Iraqi units linked up in Mosul on Saturday and will form a joint front to advance westward against the Islamic State group, officers said.

The Rapid Response Division reached the northern edge of Al-Intisar neighbourhood, while the Counter-Terrorism Service (CTS) advanced to the southern side of the adjoining Al-Quds area.

The two neighbourhoods are located on the eastern side of Mosul, where security forces have retaken multiple areas from IS, but the city's west is still completely in jihadist hands.

"God willing, Al-Intisar neighbourhood is completely liberated," Brigadier General Mahdi Abbas Abdullah, the commander of the Rapid Response Division's 2nd Brigade, told AFP.

"We will become one front" and will advance "towards the river," he said, referring to the Tigris, which divides Mosul in two.

Lieutenant Colonel Athir al-Basri of Rapid Response also confirmed its forces and those from CTS had reached the same main street that divides Al-Intisar and Al-Quds.

Iraqi forces launched the massive operation to retake Mosul on October 17, eventually pushing into the city from the east.

On Wednesday, Iraqi forces announced the "second phase" of the battle for the eastern side of the city, marking the start of a new round of intensive fighting after progress had previously slowed to a crawl.

Iraqi Prime Minister Haider al-Abadi had pledged Mosul would be retaken by year's end.

Earlier in the week, Abadi said the country would need three months to eliminate IS -- still an ambitious timeline given that it would mean retaking Mosul, clearing the jihadists out of western territory they hold, and eliminating sleeper cells in government-controlled areas.