Iraq's health minister says between 100,000 and 150,000 civilians have been killed in the war, far more than other previously accepted figures.
Dozens of bodies are brought to morgues and hospitals daily
Officials say the total is based on estimates of the number of bodies brought to mortuaries and hospitals.
Casualty figures are a controversial topic, with estimates or counts ranging from 50,000 to 650,000 deaths.
No official count has ever been made public. The health ministry is run by supporters of a radical anti-US cleric.
Speaking during a visit to Vienna, Health Minister Ali al-Shamari said the figure was based on an estimate of 100 bodies being brought into government run mortuaries and hospitals every day.
In October, the UK medical journal The Lancet published a study saying nearly 655,000 Iraqis have died as a result of the war - a far higher death toll than other estimates.
The study was dismissed by President George W Bush and other US officials as not credible. It was based on cluster samples rather than body counts.
Previous counts, such as the Iraq Body Count, held that about 50,000 had people had been killed, based on partial figures from Iraqi institutions and media reports.
This figure was informally endorsed by senior American and Iraqi officials.
The US death toll stands at more than 2,800 troops
The head of the Baghdad central mortuary said on Thursday that he was receiving up to 60 victims of violent death - from insurgent violence and sectarian strife - each day at his facility alone.
Separately, the US military says three of its personnel have been killed in two separate incidents in Iraq.
Two soldiers were hit on Thursday by a roadside bomb in western Baghdad.
In Anbar province - a focal point of Sunni Arab resistance - the Americans say a marine died on Thursday of wounds sustained in fighting.
At least 23 US troops have been killed in November. In October, at least 105 soldiers were killed, the fourth highest monthly toll since US forces overthrew Saddam Hussein, and the worst for US casualties in nearly two years.