A senior Iraqi official pushed back a September 30 deadline for pro-Iran factions to hand over their weapons, without offering an explanation for the move or providing a new date.
Iraq has come under pressure from the United States to rein in armed factions, particularly those close to Iran.
The US and Iran have been at war since February 28, drawing in other countries in the region as well as non-state groups backed by the Islamic republic.
For several months, Iraq's government has stood by its deadline, but on Sunday, the security adviser to the prime minister, Qasim al-Araji, told state media the process would only begin at the end of next month.
"September 30 is the date for the international coalition to depart, not the deadline to hand over weapons," Araji told the Al Iraqiya broadcaster, referring to the coalition of US-led forces.
Government spokesman Haider al-Aboudi had made a similar announcement to local media on Friday, despite announcing in June that factions had until the end of September to disarm.
September 30, he said, was "the date for the international coalition to end its presence, not the deadline for armed factions... Perhaps people are confusing the two."
Since taking office in May, Prime Minister Ali al-Zaidi has pledged to ensure the armed factions that emerged in the years that followed the US-led invasion hand over their weapons to the state.
While some factions have in recent weeks said they would join state institutions, others, in particular those closer to Iran, are refusing.
"The situation is extremely complicated," a government official told AFP, requesting anonymity because he was not authorized to speak on the matter.
"The government is insisting on closing the weapons file; but faction leaders are determined to hold onto their weapons because they believe disarming would serve Israel and the United States."
The most powerful armed factions in Iraq include Kataib Hezbollah, a part of Iran's so-called "Axis of Resistance" against the US and Israel.
Another Iraqi source told AFP that Iran views its proxies in the region, "especially in Iraq, as a source of strength it refuses to give up".
