Defence Secretary Gavin Williamson is understood to have promised to pay the legal costs of any soldier facing criminal charges over Bloody Sunday.
In a letter from the Ministry of Defence (MoD) to army veterans, seen by the BBC, assurances were given to the 18 former paratroopers who have been reported to the Public Prosecution Service over the 1972 killings.
It says the soldiers are represented “entirely at the Ministry of Defence’s expense”, according to the broadcaster.
Signed by Mr Williamson, the letter was sent on Tuesday night and reportedly read: “The MOD letter said soldiers are “represented by independent firms of solicitors, instructed by veterans themselves, in whose sole interest they act.
“This has been the case since the individuals were first regarded as suspects by the Police Service of Northern Ireland and will continue – without time limit or cap on expenditure – until all aspects of the investigation and subsequent legal process are complete.”
It comes on the eve of a momentous day as veterans, now in their 60s and 70s, will learn on Thursday if they are to be prosecuted over the deaths of unarmed civil rights demonstrators in Londonderry.
Thirteen people were shot and killed on the day while a 14th died a few months later with 14 others wounded.