BAGHDAD, July 1 (Xinhua) -- Iraqi Prime Minister Adel Abdul Mahdi on Monday issued a decree warning all armed groups, under the umbrella of the paramilitary Hashd Shaabi, against operating outside the official Iraqi armed forces.

"All the Hashd Shaabi forces shall operate as an integral part of the armed forces, except for provided in a special text," said the decree signed by Abdul Mahdi, who is also the commander-in-chief of the Iraqi forces.

The decree said that the Hashd Shaabi units shall sever any sort of political or administrative affiliation with any organization.

It pointed out that "the armed groups that do not join the armed forces can be turned into political organizations, which are subject to the law of parties, and laws and regulations of the political and community work, and must be prevented from carrying unlicensed weapons."

Abdul Mahdi ordered "the closure of all the headquarters that hold the names of the Hashd Shaabi groups both in the cities and outside," the decree said.

The latest decree warned that the presence of any group acting secretly or publicly outside these instructions "will be considered outlawed and liable to prosecution."

Abdul Mahdi set July 31 as a deadline for implementing the latest instructions, according to the decree.

The Hashd Shaabi was formed in late 2014 after a religious decision by top Iraqi Shiite cleric Ayatollah Ali al-Sistani to protect Baghdad and the Shiite shrines in central and southern Iraq from the threat of the extremist Islamic State (IS) militants, who seized large areas in northern and central Iraq in June 2014.

However, the Hashd Shaabi militias, which helped the Iraqi and U.S.-led international coalition forces defeat IS militants, have repeatedly been accused of being under the influence of neighboring Iran, and have a lot of influence in the Iraqi politics.