c100driver is correct, the rule is treated as unusable.
So add your normal fuel reserves to it in order to determine required fuel.
If your flight planning software does not allow you to plan for this failed item, add an adjustment for trip burn for the additional 2268kg carried as weight (~90 kg/h), then add this additional trip fuel requirement plus 2268kg to your flight plan fuel... Remember that in case of diversion this extra fuel also exists and must be taken into account for diversion fuel (time) as well.