U.S. troops and Shiite militants fought fierce battles in the Iraqi city of Najaf, where insurgents have been holed up in a mosque for nearly three weeks.

Smoke from explosions and gunfire hung over Najaf, as U.S. military forces stepped up pressure on Shiite militiamen to vacate the Imam Ali Shrine.

Witnesses say there appears to be fewer militants on the streets than in previous days. At the same time, witnesses say U.S. snipers can be seen on the rooftops around the mosque.

The shrine is unharmed, but its outer walls have been slightly damaged due to the fighting.

Speaking on the ABC television program, This Week, Iraqi National Security Adviser Mowaffaq al-Rubaie, said the interim Iraqi government wants to see the issue resolved peacefully.

"We would leave no stone unturned," he said. "We will exhaust all efforts to try to avoid violent means and security measures against the security issue."

Malaysian Prime Minister Abdullah Ahmad Badawi called on the United Nations to help stop the Najaf violence. The Malaysian leader spoke as the head of the Organization of the Islamic Conference, the world's largest grouping of Muslim nations.

Violence continued elsewhere in Iraq. The U.S. military says a total of five American soldiers have died in recent days. In Tikrit, assailants killed one Turkish citizen and two Iraqis late Sunday. In Kirkuk, unidentified gunmen killed a Kurdish official with the Patriotic Union of Kurdistan party.

Authorities reopened one of southern Iraq's major oil pipelines, which has been mostly completely shut since earlier this month because of insurgent threats to blow it up.

President Bush met Monday with top U.S. security advisers at his ranch in Texas. "We talked about Iraq, the way forward in Iraq, the way to help the Iraqis get to elections," he said. "We're making progress on the ground."

Meanwhile, Indonesian authorities are looking into reports that an Indonesian citizen was killed in an ambush Sunday in Mosul. In Nepal, the government is urging the speedy release of 12 Nepalese workers who are reported to have been kidnapped in Iraq.

Brighter news comes from the underdog Iraqi football team, which has had unexpected success at the Olympic Games in Athens. Coach Adnan Hamed acknowledged the Iraqi team is glad to be doing so well at the Olympics. But he adds that this happiness is short-lived because of the situation his country faces.

Iraq is suffering the horrors of war and destruction, Coach Hamed says, which means that as a consequence, the players feel pain and worry. He adds that even though the Iraqi football players are in Athens, they are worried about their families and friends back home.

The Iraqi team plays a semi-final match against Paraguay on Tuesday.