BAGHDAD: Sunni Arab leaders were expected to end their boycott of constitutional talks after an agreement was reached to investigate the murder of two of their colleagues drafting the document. Meanwhile, Australian Prime Minister John Howard, a top U.S. ally in Iraq, made a surprise visit to Baghdad and at least eight people died in two suicide car bomb attacks in the capital.

With just six days left for the constitutional panel to agree on a draft or call for a six-month extension of its mandate, government leaders announced agreement on conditions set by Sunni Arabs for calling off their boycott.

These included better security for representatives of the Sunni minority on the committee, and Sunni participation in a judicial investigation into the murder last Tuesday of two prominent Sunnis on the committee.

"We have already asked [the investigating judge] to open the investigation," said parliamentary Speaker Hajim al-Hasani, adding that one or two Sunni representatives would monitor the inquiry.

"A meeting of all Sunni factions will be held Tuesday morning to decide on a response, but I think that given the official statement by parliamentary Speaker Hasani there will be agreement on our immediate return" to the constitutional panel, Salim Abdallah, a member of the Sunni-based Islamic Party, said.

The boycott had threatened to derail efforts to reach a deal on the constitution in time for Parliament to vote on the draft by August 15, a deadline agreed to earlier this year. The charter is due to be put to a national referendum on October 15.

Sunni Arabs, who make up about a fifth of the population, dominated Saddam Hussein's regime and all previous Iraqi governments, but are under-represented in Parliament because much of the community boycotted the January elections.

The parliamentary constitution committee, which originally included just two Sunni MPs, brought in an additional 15 Sunni members from outside Parliament to give the disgruntled former elite a say in drawing up the new basic law.

U.S. Ambassador Zalmay Khalilzad met yesterday with constitutional committee members to urge them to reach agreement on a draft.

"It will take compromises and a willingness by each faction and community to accept less than its maximum aspirations. It is vital that a national compact be reached," his embassy quoted him as saying.

Meanwhile, the Australian prime minister held talks with Iraqi counterpart Ibrahim al-Jaafari while on a stop-over on his way back home following meetings in Washington with U.S. President George W. Bush and in London with British Prime Minister Tony Blair.

Howard "made a commitment that Australian troops will remain in Iraq for as long as required by the government and the people of Iraq," an Australian diplomat said after talks.

Australia has 900 troops in Iraq, mainly in the south.

Because of security concerns, officials refused to say if Howard was to meet with Australian soldiers in the field.

Shortly before Howard arrived, two suicide car bombers struck in Baghdad.

The first bombing targeted the Al-Sadeer Hotel in the center of the capital, a building used by foreign security personnel which had previously suffered attacks. Six people died and 16 were wounded, mostly hotel security guards.

The second bombing targeted a police commando patrol in the west of the city and left two policemen dead and 11 wounded, security officials said.

The attacks followed Sunday's massive suicide truck bombing against a police station in the southeast of the capital that killed 27 and wounded 33, many of them policemen.

In other violence, at least 15 people were killed and eight were wounded in separate rebel attacks nationwide. In other developments, two people were arrested in connection with last week's abduction of two Algerian diplomats in Baghdad, an Iraqi intelligence officer said. Armed gunmen seized Algeria's charge d'afffaires Ali Belaroussi and his colleague Ezzedin Ben Kadi on Thursday.