"Several officers involved in drafting the consolidation plan said it entailed the construction of longer-lasting facilities at the sites, including barracks and office structures made of concrete block," the paper reported.

However the officers told the Post the consolidation plan was not meant to establish a permanent US military presence in Iraq and that no timetable exists for turning over all US bases in the war-torn country.

The chief determining factor on reducing US forces in Iraq will be "the strength of the insurgency and the ability of Iraq's security services to fight it," the paper said.

Separately, a US military spokesman in Iraq said the Post's report was accurate.

"The information contained in The Washington Post article today accurately depicts the future plan for consolidation of bases in Iraq. However, as noted in the article, no timetable exists for turning over all the bases," Lieutenant Commander Gil Mendez, a US military spokesman, told AFP in Iraq.

"Any decision to begin reducing US forces will be based on the Iraqi political process continuing to move forward, and Iraqi security forces continuing to progress and develop.

"When this happens, there should be reductions in the number of troops in the coalition," Mendez said.

The Post said the consolidation plan calls for the four US military bases to eventually be centered at Tallil in southern Iraq, Al Asad in the west, Balad in central Iraq and at Irbil or Qayyarah in the north.

US forces in Iraq currently occupy 106 bases, according to the Post.

However, the article added that it remains unclear what will happen to US-run detention centers in Iraq which currently hold over 11,000 inmates.