The Cairngorms National Park Authority (CNPA) has expressed its disappointment that its objections to the construction of a new power line across part of the park have not been fully upheld.

Enterprise minister Jim Mather approved the plans, which will give developers of the scheme - Scottish and Southern Energy and ScottishPower - permission to erect 600 new pylons of up to 217ft in height along a 137-mile route between Beauly, near Inverness, and Denny, near Stirling. Mather said that he did not have the power to reroute the cable underground, as demanded by many of those against the proposal, but the approval does include conditions that 'visual impact mitigation' measures must be included at eight of the sites involved.

David Green, convener of the CNPA, said: "The CNPA recognises the need to respond to the challenges of climate change and supports the drive to maximise the amount of energy from renewable sources as the most sustainable way of providing for our future energy needs. However, sustainable energy production has to be matched by sustainable energy transmission with proper measures taken to safeguard the quality of environment between production and consumption, especially when that environment is recognised as being of outstanding national importance for its natural and cultural heritage. "The Cairngorms National Park (CNP) is such an area and the CNPA has always maintained that the preferred option would be that the pylons did not go through the CNP at all. The CNPA objected on the basis that the proposal conflicted with the statutory National Park aims and did not comply with Scottish Government planning policy and guidance and industry's own guidelines for transmission lines in such areas, since it failed to demonstrate that there are no other alternative routes.

"The CNPA and partners submitted evidence at the inquiry on the potential for undergrounding in the National Park and requested that the Scottish government facilitate discussions on alternative overhead and/or underground routes as well as the replacement of existing pylons with wooden poles in some locations in the Park. "We are very disappointed that the line will still be coming through the National Park and there is no requirement for undergrounding. However, we still welcome the fact that Scottish ministers have accepted many aspects of the case presented by the CNPA and acknowledged that the National Park is one of Scotland's special areas and is a resource for the whole nation making significant contributions to the national tourism economy.

"Although the new line will have a significant adverse impact on the landscape in part of the National Park, the removal of lines elsewhere and transfer of other lines from pylons to wooden poles, will be an enhancement which, although not offering mitigation, will compensate to a degree." In addition to the CNP, the line's construction was opposed by the four planning authorities - Highland, Stirling, Falkirk and Perth and Kinross councils - plus Clackmannanshire Council. The Beauly Denny Landscape Group, which includes the John Muir Trust, the National Trust for Scotland and Ramblers Association Scotland, have all protested at the environmental damage they believe the giant pylons will cause.