Oil production, which is the backbone of the country's economy, has been staying below prewar level while public services, including clean water, electricity and cooking gas, are nowhere near satisfactory performance.

The International Committee of the Red Cross said Monday that "the humanitarian situation in most of the country is among the most critical in the world."

The organization said in some areas of the country, people have no functioning water and sanitation facilities, and the poor public water supply has forced some families to use at least a third of their average 150 US dollars monthly income to buy clean drinking water.

Bush defending war

US President George W. Bush Wednesday defended the Iraq war as a "right decision" despite the high cost in a speech at the Pentagon as thousands of Americans staged anti-war demonstrations across the nation to mark the war's fifth anniversary.

"Removing Saddam Hussein from power was the right decision, and this is a fight America can and must win," Bush said. With six sentences began with "because we acted," he bragged about how the war "benefited" Iraqi people by ending Saddam's regime.

The US president acknowledged that the war has "come at a high cost in lives and treasure," but said "those costs are necessary when we consider the cost of a strategic victory for our enemies in Iraq."

Nobel Prize-winning economist Joseph E. Stiglitz and Harvard University public finance expert Linda Bilmes have reportedly estimated the total bill of the war could be as much as 3 trillion dollars when all the expenses are calculated.

Bush underlined that the United States still face an uphill task ahead. "There's still hard work to be done in Iraq. The gains we've made are fragile and reversible."

Violence in Iraq has dropped down 60 percent since last June after the United States added an extra 30,000 troops, according to US and Iraqi officials.