Iraqi forces attacked a desert outpost of the Islamic State group near the Syrian border Saturday in preparation for a drive up the Euphrates Valley towards the frontier, commanders said.

The assault targeted the former mining town of Akashat, in mainly Sunni Arab Anbar province some 100 kilometres (60 miles) south of the jihadists' border bastion of Al-Qaim.

Al-Qaim and the Euphrates towns of Rawa and Anna downstream form just one of two enclaves still held by IS in Iraq after a string of battlefield defeats this year.

"The army, the Hashed al-Shaabi (Popular Mobilisation force) and the border guard launched a major operation to liberate Akashat... and secure the border to its north," said the head of Joint Operations Command, General Abdelamir Yarallah.

The Hashed al-Shaabi are a paramilitary force largely composed of Iran-trained Shiite militias but also including some fighters recruited from Sunni tribes.

Iraqi commanders estimate there are no more than 300 civilian families left in Akashat, a former railhead that was once a major source of phosphate production.

Imed Meshaal, mayor of Rutba, a desert town further south recaptured from IS last year, told AFP the jihadists had turned the area into a major hub for arms caches, training camps and command centres.

Iraqi commanders say they estimate IS still has more than 1,500 fighters in its Al-Qaim enclave.

The jihadists also control a second enclave west of the ethnically divided Kurdish-held city of Kirkuk centred on the mainly Sunni Arab town of Hawija.

A promised offensive against IS there has been delayed by a row over a controversial referendum on Kurdish independence planned for later this month.

Source: AFP