The Royal Netherlands Navy and Belgium Navy decided to upgrade the four frigates by rebuilding both hangar and helicopter deck for the NH-90 as well to replace the forward mast for fitting the new Thales SeaWatcher 100 phased array surface search radar and Gatekeeper electro-optical surveillance system. The first ship to receive the upgrade was HNLMS Van Speijk F828 in April 2012, next was BNS Leopold I F930, followed by HNLMS Van Amstel F831 and BNS Louise Marie F931 is currently undergoing the modernization. SMART-S 3D search radars will not be replaced by SMART-S MK2.