The two million-word report, six years in the making, will be unveiled by Sir John Chilcot on Thursday (NZT).
Tony Blair, prime minister when Britain went to war, has said he will not make any comment until the report is made public.
The International Criminal Court (ICC) has indicated the former Labour leader will not be liable for prosecution, reiterating its conclusion 10 years ago that the decision to go to war is not within its jurisdiction.
The court said it will look at the report's findings before deciding whether there is a "reasonable basis" to begin an investigation.
A number of MPs are expected to try to use an ancient law to try to impeach the former prime minister once the findings are published.
Former Scottish First Minister Alex Salmond said there "has to be a judicial or political reckoning" for Blair's role in the Iraq conflict while shadow chancellor John McDonnell said the "processes" of how Britain ended up at war must be examined "so we never ever get into this tragic, tragic mess again with such loss of life".
Some of those whose loved ones died in the war between 2003 and 2009 fear the report will not give them the answers they desperately want.
His mother Julia said: "It will be a whitewash. I'm absolutely disgusted. I'm not going because it will be a whitewash.
"Tony Blair has got blood on his hands. He will have covered his back and (George) Bush's back."
The Chilcot inquiry was set up in 2009 by then prime minister Gordon Brown after the withdrawal of the main body of British troops earlier that year.
The inquiry examined the lead up to the 2003 invasion, and the years up to the 2009 withdrawal.
The report's long-awaited publication follows 130 sessions of oral evidence and the testimony of more than 150 witnesses.
The inquiry has analysed more than 150,000 government documents as well as other material related to the invasion.
Relatives of the service personnel killed in Iraq between 2003 and 2009 will get an early sight of a 150-page summary.
David Godfrey, whose grandson Daniel Coffey, 21, was killed in 2007, said: "I'm quite apprehensive at the moment.
"People say this should bring closure but it won't. It might give us information but what we need is closure.
"It can't bring anybody back and won't stop us feeling what we feel. It's just another step forward on another long journey."
He branded Mr Blair a "war criminal" and said "he has to be held responsible".
The families of some British
soldiers killed in the Iraq war say they will boycott the Chilcot
inquiry over fears it will be a “whitewash.”
The two million-word inquiry report about the involvement of the British government in the 2003 invasion of Iraq will be published on Wednesday after about seven years.
The Iraq Inquiry, also referred to as the Chilcot Inquiry after its chairman, Sir John Chilcot, was established in 2009 to investigate Britain’s role in the Iraq war and its aftermath that saw British forces remain in the Arab country for six years.
The report analyzes evidence about how the government of Labour Prime Minister Tony Blair acted before the invasion of Iraq and during the war.
Relatives of the 170 British soldiers who were killed between 2003 and 2009 will get an early sight of a summary of the report.
"It will be a whitewash. I'm absolutely disgusted. I'm not going because it will be a whitewash,” said Julia Nicholson, mother of Gary Nicholson who died when their plane was shot down in 2005.
"Tony Blair has got blood on his hands. He will have covered his back and (George W) Bush's back," she added.
Janice Procter, whose 18-year-old son Michael Tench was killed in 2007, said "It's been horrendous, I'm very apprehensive about this.”
"This man (Blair) has put 179 kids to the slaughter – there's no justice. (The report) is not going to give me any closure or comfort," she said.
Procter added that she will not attend the session for the relatives of the soldiers, “I'm not going to waste two hours of my life reading it."
David Godfrey, whose grandson Rifleman Daniel Coffey died in 2007 in Iraq, said Blair is a “war criminal” and should be tried at a court.
"I'm quite apprehensive at the moment. People say this should bring closure but it won't. It might give us information but what we need is closure,” Godfrey said.
Roger Bacon’s son Matt was killed in the war in 2005. Bacon said, "What I'm expecting is that the report will bring out what I've always believed, which is that [Blair] took us to war illegally.”
“The major thing is, how did we get into this mess in the first place?” he added.
Blair told British MPs before invading Iraq that intelligence showed former Iraqi dictator Saddam Hussein had “active”, “growing” and “up and running” nuclear, biological and chemical weapons. Weapons of mass destruction (WMD) were the basis of launching the war.
In 2004, however, a US report said that Saddam Hussein had destroyed his last WMD over a decade ago and had no capacity to build new ones.
Earlier reports said that the Chilcot inquiry report will affect the reputation of Blair, his foreign secretary Jack Straw and former MI6 chief Richard Dearlove.
Launched by the administration of former US president George W. Bush with strong UK backing, the war led to the deaths of more than one million Iraqis.
The invasion plunged Iraq into chaos, resulting in years of deadly violence and the rise of terrorist groups like Daesh (ISIL).
The two million-word inquiry report about the involvement of the British government in the 2003 invasion of Iraq will be published on Wednesday after about seven years.
The Iraq Inquiry, also referred to as the Chilcot Inquiry after its chairman, Sir John Chilcot, was established in 2009 to investigate Britain’s role in the Iraq war and its aftermath that saw British forces remain in the Arab country for six years.
The report analyzes evidence about how the government of Labour Prime Minister Tony Blair acted before the invasion of Iraq and during the war.
Relatives of the 170 British soldiers who were killed between 2003 and 2009 will get an early sight of a summary of the report.
"It will be a whitewash. I'm absolutely disgusted. I'm not going because it will be a whitewash,” said Julia Nicholson, mother of Gary Nicholson who died when their plane was shot down in 2005.
"Tony Blair has got blood on his hands. He will have covered his back and (George W) Bush's back," she added.
Janice Procter, whose 18-year-old son Michael Tench was killed in 2007, said "It's been horrendous, I'm very apprehensive about this.”
"This man (Blair) has put 179 kids to the slaughter – there's no justice. (The report) is not going to give me any closure or comfort," she said.
Procter added that she will not attend the session for the relatives of the soldiers, “I'm not going to waste two hours of my life reading it."
David Godfrey, whose grandson Rifleman Daniel Coffey died in 2007 in Iraq, said Blair is a “war criminal” and should be tried at a court.
"I'm quite apprehensive at the moment. People say this should bring closure but it won't. It might give us information but what we need is closure,” Godfrey said.
Roger Bacon’s son Matt was killed in the war in 2005. Bacon said, "What I'm expecting is that the report will bring out what I've always believed, which is that [Blair] took us to war illegally.”
“The major thing is, how did we get into this mess in the first place?” he added.
Blair told British MPs before invading Iraq that intelligence showed former Iraqi dictator Saddam Hussein had “active”, “growing” and “up and running” nuclear, biological and chemical weapons. Weapons of mass destruction (WMD) were the basis of launching the war.
In 2004, however, a US report said that Saddam Hussein had destroyed his last WMD over a decade ago and had no capacity to build new ones.
Earlier reports said that the Chilcot inquiry report will affect the reputation of Blair, his foreign secretary Jack Straw and former MI6 chief Richard Dearlove.
Launched by the administration of former US president George W. Bush with strong UK backing, the war led to the deaths of more than one million Iraqis.
The invasion plunged Iraq into chaos, resulting in years of deadly violence and the rise of terrorist groups like Daesh (ISIL).
