Sunni Arab politicians called for a government of national unity Saturday and signaled they will use their increased numbers in parliament to curb the power of rival Shiites, who have claimed the biggest number of seats in the new legislature.

At least 12 Iraqis were killed in a spate of bombings and shootings across the country. Three policemen died in a car bombing in Baqouba, 35 miles northeast of Baghdad, and Britain announced that a security contractor was killed in a roadside bombing.

A car bomb exploded midday near the crowded Medina Market in eastern Baghdad's Shaab neighborhood, killing one person and wounding six, police Maj. Awad Eitan said. One shop was destroyed by the blast.

Five bodyguards of President Jalal Talabani also were wounded in a roadside bomb blast in northern Iraq, police said Saturday. Talabani was not with them at the time.

Official returns released Friday from the Dec. 15 national election confirmed that the coalition of Shiite religious parties that dominates the outgoing government again won the biggest number of seats in the new parliament — but not enough to govern without partners.

The Shiite alliance took 128 of the 275 seats, the election commission said. An alliance of two Kurdish parties allied with the Shiites in the outgoing government won 53 seats.

Sunni Arabs, virtually shut out of the current assembly, scored major gains, opening the door to a greater role in government for the community at the heart of the insurgency. The Friday announcement paves the way for intensive negotiations to form a new government.

U.S. officials are urging formation of a broad-based government of Shiites, Sunnis and Kurds, hoping that will lure insurgents away from violence so that U.S. and other foreign troops can begin withdrawing.

In separate press conferences Saturday, two leading Sunni Arab politicians expressed their interest in joining a coalition government. But they made clear they will insist on curbing the trend toward sectarianism, which many Sunnis blame on policies of the outgoing government led by Shiites and Kurds.

Two major Sunni Arab groups took a total of 55 seats. Only 17 Sunni Arabs serve in the outgoing parliament.

"We will participate actively in the political process and we will cooperate with many political entities that share us the same principles," said Adnan al-Dulaimi, whose Iraqi Accordance Front won 44 seats.

"We believe in achieving stability, halting random arrests, releasing all detainees, eliminating sectarianism and preventing any sectarian group from dominating the government and rule the country in a dictatorial manner."

Saleh al-Mutlaq, leader of a separate Sunni group that won 11 seats, pledged to work toward formation of "a government of national unity" that would combat sectarianism.

After the results are ratified in about two weeks, Talabani has 15 days to convene parliament, which must choose a new president within a month. The new president designates a prime minister from the Shiite bloc, who must present his Cabinet to parliament for approval within a month.

The Shiites need only a majority in parliament to approve their prime minister, but a higher threshold to elect a president means they need more partners to govern smoothly.