Barristers in Northern Ireland have withdrawn from all new criminal cases requiring legal aid in protest against new rules reducing the level of payments.
The Criminal Bar Association said it was taking the move "with deep regret".
Barristers will continue with cases that began before the rules came into effect earlier this month.
Stormont Justice Minister David Ford says his new legal aid rules are essential and fair.
The barristers' move follows the withdrawal last week by the largest criminal law firm in Northern Ireland from all major cases.
Kevin Winters & Company last year carried out more legal aid work than any other law firm in Northern Ireland and received payments of just over £2m.
'Substantial and unjustified'
In a statement on Tuesday, the Criminal Bar Association, which represents independent barristers, said it was "committed to providing the highest standard of representation to those members of society who face the most serious and complex criminal cases in the Crown Court".
It said those standards "cannot be achieved under these amended rules".
It described the cuts as "substantial and unjustified".
"Whilst the Criminal Bar Association recognises the financial restriction occasioned by pressure on public spending, these latest proposals represent cuts of almost 50% from levels previously set by the Department of Justice in 2005," its chairman Gavan Duffy said.
"These rules will inevitably dilute the quality of representation available to some of the most vulnerable members of society and to the victims of crime."
Last week, it emerged that the Law Society and bar council were joining forces in legal action, taking the justice minister to court in an attempt to have his new rules overturned.