LONDON, April 16 (Reuters) - Allegations British troops unlawfully killed up to 20 Iraqi men at an army camp in 2004 were part of a conspiracy to pervert the course of justice, the British government told a public inquiry into the deaths on Wednesday.
The British authorities have said that the 20 Iraqis were "armed insurgents" who were killed on the battlefield. However, relatives and local residents have said the men were captured alive and later executed and mutilated at the military camp.
"The untruthful allegations cannot be attributed to honest mistakes or misunderstandings," lawyers for Britain's Ministry of Defence said in a closing submission to the inquiry, which has cost at least 27 million pounds ($45 million).
"They are the product of a conspiracy between a number of the Iraqi core participants to pervert the course of justice."
Almost three years after the final British troops left Iraq in 2011, costly inquiries about the war have helped keep alive a public debate about why Britain got involved in the U.S.-led invasion of Iraq and how the war was conducted.
Lawyers for the ministry said allegations that the men's bodies had been mutilated were "demonstrably unfounded" and "dishonestly made".
Despite their allegations, lawyers for relatives of the dead Iraqis said last month there was insufficient evidence to back their clients' main claim of unlawful killing, which relates to events during and after a battle in southern Iraq on May 14, 2004.
However, the long-running Al-Sweady inquiry into the matter has continued and is also looking at separate allegations that soldiers mistreated up to nine detainees.
Describing the allegations as "patently untrue", the ministry did however say there were some instances in which the conduct of British soldiers fell below expected standards, including one detainee being shouted at and possibly slapped. ($1 = 0.5955 British Pounds) (Reporting by Kylie MacLellan; Editing by Andrew Osborn)