BAGHDAD, (AP) – Representatives of Iraq’s major political parties on Sunday strongly denounced a U.S. Senate proposal calling for a limited centralized Iraqi government with the bulk of the power given to the country’s ethnically divided regions.

The groups, which represented both Shiites and Sunnis, said the plan would hamper Iraq’s future stability, and they suggested parliament draft a law permanently banning the splitting of Iraq along sectarian or ethnic lines.

“This proposal was based on the incorrrect reading and unrealistic estimations of Iraq’s past, present and future,” according to the statement read by Izzat al-Shahbandar, a representative of the Iraqi National List, a secular political party.

The nonbinding Senate resolution calls for Iraq to be divided into federal regions under control of Kurds, Shiites and Sunnis in a power-sharing agreement similar to the one that ended the 1990s war in Bosnia. Sen. Joseph Biden, D-Del., was a prime sponsor of the measure.

The Kurds in three northern Iraqi provinces are running a virtually independent country within Iraq, while nominally maintaining relations with Baghdad. They support a formal division, but both Sunni and Shiite Muslims have denounced the proposal.

The majority Shiites, who would retain control of major oil revenues under a division of the country, oppose the measure because it would diminish the territorial integrity of Iraq, which they now control. Sunnis would control an area with few if any oil resources. Kurds have major oil reserves in their territory.

Al-Shahbandar said at a news conference the proposal “opposes all laws of the international community and its legitimate institutions which protect all the rights of people in self-decision, building their future and defending their unity and sovereignty.”

He added that the international community should denounce the proposal and “support Iraq in its crisis and its efforts to restore security and stability in all its areas.”

On Friday, Prime Minister Nouri al-Maliki told The Associated Press that “dividing Iraq is a problem, and a decision like that would be a catastrophe.

Iraq’s constitution lays down a federal system, allowing Shiites in the south, Kurds in the north and Sunnis in the center and west of the country to set up regions with considerable autonomous powers.

Nevertheless, ethnic and sectarian turmoil have snarled hopes of negotiating such measures, especially given deep divisions on sharing the country’s vast oil resources. Oil reserves and existing fields would fall mainly into the hands of Kurds and Shiites if such a division were to occur.

Also Sunday, a judge delayed court proceedings for a second U.S. Army sniper accused in the deaths of two unarmed Iraqi civilians a day after a military panel sentenced a 22-year-old specialist to five months in prison for his role in the crimes.

Jorge G. Sandoval was convicted Thursday of planting evidence on one of the unidentified Iraqis who died last spring. He was acquitted of two murder charges.

Sandoval had faced five charges in the deaths of the two unidentified Iraqi men. In dramatic testimony during the four-day court-martial, his colleague, Sgt. Evan Vela, testified he had pulled the trigger and killed one of the men Sandoval was accused of murdering.

Vela said the sniper team was following orders when it shot the men during two separate incidents near Iskandariyah, a Sunni-dominated area south of Baghdad, on April 27 and May 11.

Vela, 23, was expected to undergo a pretrial hearing Sunday until a military judge decided to postpone those proceedings for at least a month. Vela’s civilian defense lawyer had asked that the hearing be closed to the media because of classified information expected to be discussed.