The human rights organisation's report covers the first five months of the year and comes days after a declaration by the Iraqi government of a "total victory" over the extremists in the city.
The liberation of Mosul "underscores the success of the worldwide effort led by the Iraqi Security Forces", Tillerson said in a statement. "ISIS was holding all the cards, if you will, on the civilian population that remained in that final holdout [in Mosul]".
The fight dealt a huge blow to IS's so-called territorial caliphate, but has also killed thousands, left entire neighbourhoods in ruins and displaced almost 900,000 people from their homes.
"Many of the people who are in that situation are too weak even to cross the front line".
In a statement issued by Abadi, he announced "the end and the failure and the collapse of the terrorist state of falsehood and terrorism which the terrorist Daesh announced from Mosul".
Two Iraqi television journalists were killed by the Islamic State group while a third was trapped today in the same village south of Mosul.
Now, they have to return to their home, a home of rubble.
Earlier in the day, airstrikes pounded the last IS-held territory on the western edge of the Tigris, Humvees rushed wounded to field hospitals and soldiers hurriedly filled bags with hand grenades to ferry to the front.
The Associated Press said IS mortar shells had also landed near Iraqi troops.
The coalition's attacks were largely carried out with Improvised Rocket Assisted Munitions (IRAMs), explosives with unsophisticated targeting abilities, which "wreaked havoc in densely-populated west Mosul and took the lives of thousands of civilians", according to the report.
He estimated that rebuilding the Old City alone would cost $1 billion.
A coalition spokesperson said Amnesty's findings were "irresponsible and an insult".
"The question is whether the Iraqi government will be able to address the human right violations", he said from London. Army Lt. Gen. Stephen Townsend, the commander of the anti-ISIS coalition, said Tuesday about 25 percent of West Mosul sustained heavy, often irreparable damage during the battle and another 25 percent sustained moderate damage.
"We started on the east side because we thought it would be easier there", he said from Baghdad.
"ISIS's use of people as human shields does not lessen the legal obligation of pro-government forces to protect civilians", says Maalouf.
Momani, who is also the government spokesman, congratulated the government and the people of Iraq on the "historic achievement", praising the ultimate sacrifices given by "our Iraqi brethren" in their confrontation with criminal gangs.