Islamic State group jihadists battled Iraqi forces near Ramadi west of Baghdad Wednesday after infiltrating government lines, a military source said.

"Terrorists infiltrated the Al-Tash and Majr areas south of Ramadi as well as the Kilometre Seven District west of the city," a general who asked not to be identified told AFP.

Ramadi is the capital of the vast, mainly Sunni Arab Anbar province, which has long been a bastion of insurgency and was retaken by the army from IS only in December 2015.

Troops and paramilitaries last week launched twin offensives against the jihadists' last footholds in Iraq -- in the Euphrates Valley near the Syrian border and around the northern town of Hawija