Two anti-corruption groups have convinced a British court to delay final approval of a controversial plea bargain between the U.K. Serious Fraud Office and arms company BAE Systems, complicating closure of what had already been a much-criticized prosecution.

The ruling, issued March 2, means that BAE cannot plead guilty to the charges it agreed with the SFO until the protesters have had a chance to make their case later this month that the plea deal should be struck out.