(Adds Odierno comment)
By Peter Graff and Waleed Ibrahim
BAGHDAD, Dec 2 (Reuters) - Iraq must take advantage of improved security and enact laws aimed at national reconciliation or risk a resumption of sectarian bloodshed, U.S. Deputy Secretary of State John Negroponte said on Sunday.
Violence has fallen sharply over the past few months in Iraq after Washington deployed an additional 30,000 troops. But Iraqi leaders have so far made scant progress passing laws aimed at reconciling majority Shi’ites and minority Sunni Arabs.
Political tensions also escalated in recent days after the largest Sunni Arab bloc walked out of parliament to protest what it said was the house arrest of their leader, Adnan al-Dulaimi. The bloc called off the boycott on Sunday when Dulaimi was allowed to leave his house for the first time in three days.
"The security surge has delivered significant results," Negroponte told a news conference in Baghdad at the end of a six-day tour of Iraq.
"Now progress on political reconciliation, including key national legislation as well as economic advances, is needed to consolidate the gains. If progress is not made on these fronts we risk falling back toward the more violent habits of the past."
With attacks at their lowest levels in nearly two years, attention has focused on whether the Shi’ite-led government of Prime Minister Nuri al-Maliki can reach an accommodation with disaffected Sunni Arabs.
In a sign of the sectarian divide, the Sunni Arab Accordance Front called the boycott of parliament after Dulaimi was confined to his house following the arrest of his son and dozens of bodyguards on suspicion of links to a car bomb.
But Dulaimi was escorted from home on Sunday by National Security Adviser Mowaffaq al-Rubaie and brought to a hotel in the heavily fortified "Green Zone" government and diplomatic compound, where he called an end to the boycott.
"Since this house arrest has been lifted, the Accordance Front will return to sessions of parliament," he told an Iraqi television station.
Dulaimi’s daughter Asmaa al-Dulaimi, also a member of parliament, told Reuters her father had agreed to stay at the hotel opposite the parliament building until Thursday.
She said Rubaie had promised in that time to complete an investigation into the affair, which began last week when Iraqi police and soldiers chased suspected gunmen into Dulaimi’s office compound. They found a car bomb nearby, and U.S. forces said one of Dulaimi’s bodyguards had the key to the vehicle.
Dulaimi’s bloc has been a heavy critic of Maliki’s government and pulled its members from a national unity cabinet in August, saying Sunni Arabs were being marginalised.
Negroponte declined to comment on the Dulaimi affair but said he was optimistic Iraq would achieve political reconciliation. Sceptics should bear in mind the recent improvements in security, he said.
His thoughts were echoed by the second-ranking U.S. commander in Iraq, Lieutenant-General Raymond Odierno.
"They have not accomplished what we would like them to do. They’re probably not doing it as quickly as we’d like. But they are starting to take steps," Odierno said during an interview on CNN’s Late Edition.
The main laws Washington wants passed include measures to reform a law banning former members of Saddam Hussein’s Baath party holding office, agreeing how to equitably share Iraq’s oil wealth and setting a date for provincial elections.
The lack of legislative progress contrasts with the gains made on the security front.
Government figures released at the end of last week showed 537 civilians were killed in November, a fall of 29 percent from October and the lowest since before sectarian violence exploded following an attack on a Shi’ite shrine in February 2006.
Apart from the impact of beefed-up U.S. troop numbers, military commanders credit the reduced violence to the growth of informal neighbourhood police units and a ceasefire by the Mehdi Army militia of anti-American cleric Moqtada al-Sadr. (Additional reporting by Alaa Shahine)