BAGHDAD -- President Obama praised Iraqi moves to form an "inclusive" government on Friday, but a two-day-old power-sharing deal was already looking fragile after Sunni lawmakers walked out of parliament, clouding the possibilities for working with Shiite Prime Minister Nouri al-Maliki.

Members of the Sunni-backed Iraqiya bloc have accused al-Maliki's Shiite coalition of breaking promises under the deal, which aimed to break an eight-month deadlock and allow the creation of a new Iraqi government. Sunni lawmakers said they intended to press al-Maliki for explanations on Friday.

The power-sharing agreement paved the way for a parliament session Thursday in which the first steps were taken toward forming the new government: Lawmakers re-elected Kurdish leader Jalal Talabani as president, and he then asked al-Maliki to start putting together his coalition administration, a process that could take several weeks.

But the session was marred by the walkout by most of Iraqiya's lawmakers, including the bloc's leader, Ayad Allawi, the man who wanted the prime minister spot.

The agreement gives Sunnis a role in the new government and gives Allawi a position as head of a still-undefined council to handle security affairs. But that fell far short of Sunni ambitions for greater political power after years of governments dominated by religious Shiite parties. Their hopes had been further raised because Iraqiya narrowly won the March 7 parliament elections, taking the most seats of any bloc but not a majority.

Washington has sought a greater Sunni role in the new government, fearing that otherwise disillusioned members of Iraq's Sunni minority could turn toward the insurgency, fueling violence.

At a press conference in Seoul, Obama praised the progress. "All indications are that the government will be representative, inclusive, and reflect the will of the Iraqi people who cast their ballots in the last election," he said.

"For the last several months, the United States has worked closely with our Iraqi partners to promote a broad-based government," he said. "Now Iraq's leaders must finish the job of forming their government so they can meet the challenges that a diverse coalition will inevitably face."

Obama was to speak Friday with al-Maliki, a day after speaking with Allawi, said Ben Rhodes, deputy national security adviser. In his conversations, Obama "stressed the need for Dr. Allawi, other members of Iraqiya, and representatives from all of the winning blocs to hold leadership positions," Rhodes said.

Obama made no mention of the Sunni walkout; a U.S. official speaking on condition of anonymity late Thursday because of the sensitivity of the talks downplayed the walkout. He attributed it to political showmanship but acknowledged the fragile nature of the agreement for the two sides to work together.

The Iraqiya walkout on Thursday was prompted after lawmakers rejected a demand from the bloc that parliament vote on reversing decisions by Iraq's de-Baathification commission barring three of the bloc's members from government posts. Iraqiya says that under the agreement, the factions have committed to get rid of the controversial de-Baathification law entirely within two years. Sunnis view the panel, which purges former members of Saddam Hussein's ruling party, as a thinly veiled Shiite attempt to disenfranchise Sunnis.

The walkout may not derail the power-sharing agreement, but it underscored the deep mistrust Sunnis feel toward al-Maliki and his Shiite allies -- and indicated that the process of forming a government will be tumultuous and that any government that emerges could be deeply fractured.

Allawi's alliance narrowly defeated al-Maliki's bloc at the March 7 election. But no single list won the majority needed to the rule outright, leaving the two rivals scrambling for allies. Al-Maliki now holds the parliamentary majority after gaining support for the Kurds and the followers of the anti-American Shiite cleric Muqtada al-Sadr.