The British government will announce an inquiry into the war in Iraq this week, media reported Sunday.
The move is expected to be confirmed in a statement to parliament, the Observer newspaper and Press Association domestic news wire said, quoting unnamed sources. It will probably come as early as Tuesday, the Observer said.
The probe is set to be announced days after Prime Minister Gordon Brown fended off a crisis which threatened his leadership prompted by historically bad results in European and local election results on June 4.
A new You Gov/Sunday Times poll gave Brown's ruling Labour party 24 percent support compared to 40 percent for the main opposition Conservatives led by David Cameron.
The inquiry will likely examine the circumstances leading up to Britain's decision under Brown's predecessor Tony Blair to join the US-led invasion in March 2003, and its aftermath.
Foreign Secretary David Miliband said in March that an inquiry would be held soon after all but a handful of Britain's 4,100 troops withdraw from Iraq by an agreed date of July 31.
The government now faces controversy over whether or not the probe will be held in private, as Miliband has indicated.
Opposition politicians and relatives of British soldiers killed in Iraq are urging full transparency.
Nick Clegg, leader of the second opposition centrist Liberal Democrats, said the probe would be seen as a sham unless those conducting it were given full access to all documents, could subpoena witnesses and look back to at least a year before the war began.
"If he (Prime Minister Gordon Brown) holds it all or partly in secret and kicks the eventual report into the long grass, it will be a betrayal of all those families who lost children serving in Iraq," Clegg told the Observer.
"They need answers, not another Whitehall stitch-up."
Anti-war campaigner Rose Gentle, whose soldier son Gordon died in Iraq, told the paper: "We already feel that we've been lied to by the government. We don't want any more lies."
A total of 179 British personnel have died serving in Iraq since March 2003.
Earlier this month, Brown faced a wave of resignations by senior ministers and calls for him to quit following the heavy election defeats.
Labour had already been hit hard by a scandal over lawmakers' expense claims.
But no figure emerged to challenge him and he held on, although Business Secretary Lord Peter Mandelson -- effectively Brown's deputy -- warned Saturday that he could still face fresh challenges later this year.
The YouGov/Sunday Times opinion poll also said that 51 percent of people believe Brown's continued presence as premier is damaging Britain, while 60 percent said Brown should quit now or before the next general election, which must be held by the middle of next year.
YouGov interviewed 1,902 people online on June 11 and 12.