Iraqi authorities claimed on Tuesday to have freed 888 prisoners in two weeks to placate month-long rallies in the country's Sunni areas that have hardened opposition against the Shiite prime minister.

The demonstrations come amid a political crisis that has pitted Prime Minister Nuri al-Maliki against several of his erstwhile government partners just months ahead of provincial elections.

The protesters have railed against the alleged exploitation of anti-terror laws by the Shiite-led authorities to target their minority community and demanded the release of prisoners they say were wrongfully detained.

Deputy Prime Minister Hussein al-Shahristani told a news conference in Baghdad on Tuesday that 888 prisoners had been freed since January 7, with a further 1,041 prisoners released on bail. He promised the releases would continue on a daily basis.

Shahristani said priority would be given to female detainees when it came to being discharged on bail.

The move has formed the centrepiece of the government's response to rallies in western and northern Iraq, with Shahristani also apologising this month for authorities holding detainees without charge for prolonged periods.

Officials have not provided any breakdown of the prisoners freed, and have not given details on how many had finished jail terms and how many had been held without charge.

Anti-government rallies have been ongoing since December 23 in mostly Sunni areas of Iraq, with the longest-running of the protests blocking off a key highway linking Baghdad to Jordan and Syria.