The Government has insisted it will fight a bid to trigger prosecutions of former ministers and senior military figures over alleged war crimes in Iraq.
A complaint filed with the International Criminal Court (ICC) has accused British forces of abusing and killing detainees in their custody.
The head of the army, General Sir Peter Wall, ex-defence secretary Geoff Hoon, and former defence minister Adam Ingram are among those named in the 250-page dossier, according to the Independent on Sunday.
Human rights lawyers have drawn on the cases of more than 400 Iraqis, arguing they represent "thousands of allegations of mistreatment amounting to war crimes of torture or cruel, inhuman or degrading treatment".
They describe incidents ranging from "hooding" prisoners to burning, electric shocks, threats to kill and "cultural and religious humiliation".
Other forms of alleged abuse between 2003 and 2008 include sexual assault, mock executions, and threats of rape, death, and torture.
The formal complaint to the ICC was lodged yesterday by Public Interest Lawyers (PIL) and the European Centre for Constitutional and Human Rights (ECCHR).
It calls for an investigation into the alleged war crimes under Article 15 of the Rome Statute.
The dossier says "those who bear the greatest responsibility" for alleged war crimes "include individuals at the highest levels" of the British Army and political system.
UK military commanders "knew or should have known" that forces under their control "were committing or about to commit war crimes".
Meanwhile, it argues that "civilian superiors knew or consciously disregarded information at their disposal, which clearly indicated that UK services personnel were committing war crimes in Iraq".
However, the Ministry of Defence insisted all the issues had already been examined or were being examined in this country.
"These matters are either under thorough investigation or have been dealt with through various means including through the Iraq Historic Allegations Team, independent public inquiries, the UK and European courts and in Parliament," a spokesman said.
"As such, further action through the ICC is unnecessary when the issues and allegations are already known to the UK Government, action is in hand and the UK courts have already issued judgments.
"Should we be approached by the ICC, we will take the opportunity to explain the very extensive work underway to deal with historic allegations of abuse.
"We reject the suggestion that the UK's Armed Forces - who operate in line with domestic and international law - have systematically tortured detainees.
"But of course the UK Government regrets the small number of cases where abuses have taken place.
"Wherever allegations have been substantiated, we have compensated victims and their families."
Lawyers at the Berlin-based ECCHR have been litigating against American military and civilian officials over alleged illegal interrogation policies on behalf of Iraqi and Guantanamo detainees who suffered torture and other crimes while in US detention.
PIL is currently acting for more than 1,069 former detainees and surviving relatives who allege that they or their family members were unlawfully detained, tortured, or killed by UK service personnel in Iraq.
The firm represented the family of Baha Mousa and is also representing alleged victims of mistreatment in Iraq at the long-running Al-Sweady Inquiry into incidents after the Battle of Danny Boy in southern Iraq in May 2004.
It has also been behind attempts to force the Government to hold a wider inquiry into general allegations of unlawful killing and abuse by UK troops.
Last year, High Court judges said a ''new approach'' was required relating to the Government's inquiry into the allegations, which is currently being carried out by the independent Iraq Historic Allegations Team (IHAT).
In May the judges called for mini-inquiries, akin to inquests, to take place in possibly scores of cases to fulfil the requirements of Article 2, which relates to the obligation to investigate suspicious deaths involving the state.
The judges were told that there might be as many as 150-160 cases involving deaths, as well as 700-800 involving mistreatment of civilians in breach of Article 3 of the European Convention on Human Rights, which prohibits inhuman and degrading treatment.