The MoD has succeeded in overturning the decision by Comhairle nan Eilean Siar to give the go-ahead for the three wind turbine projects in Uist.
The MoD had raised judicial review proceedings at the Court of Session over the outcome of Comhairle committee meetings which approved the developments at Bornish and Frobost on South Uist last year.
The MoD originally objected on the basis that the wind turbines would cause interference to the Range Control Radars on South Uist and St Kilda and the Air Defence Radar at South Clettraval in North Uist.
Objections from the MoD in regards to turbine plans have caused frustration across Uist for halting development in the islands.
A Comhairle spokesperson explained: “The Comhairle resolved in February not to oppose these Petitions.
“The Petitions were granted yesterday morning, and the planning permissions are accordingly void.
“This has the effect that the planning applications now require to be dealt with again by the Comhairle, taking into account any new information received.”