The first steps towards setting up Scotland�s third national park were taken yesterday � on the day Scottish ministers announced the boundaries of Britain�s biggest park are to be extended.

The first steps towards setting up Scotland's third national park were taken yesterday - on the day Scottish ministers announced the boundaries of Britain's biggest park are to be extended.

The North Harris Trust, which owns 62,500 acres in the north of the island, has written to every Harris resident to kickstart a debate over whether the community should seek the designation for its natural and human habitats.

Last night, the trust said it was inviting every resident to meetings to begin a process which could end in the island becoming a national park.

Meanwhile, Environment Minister Mike Russell delighted campaigners by announcing the boundaries of the Cairngorms National Park are to be increased to take in Blair Atholl and parts of eastern and Highland Perthshire.

He heralded the moves as he opened Holyrood's debate on national parks yesterday.

Mr Russell said the two existing parks, Cairngorms and Loch Lomond and the Trossachs, would be reviewed to ensure they were being run efficiently and effectively.

Their planning powers will be examined, as will their boundaries.

But Mr Russell said he would not wait before tackling the long-standing sense of grievance in much of Perthshire over its exclusion from the Cairngorms park.

He said: "A strong case has already been made for extending the southern boundary of the Cairngorms National Park. Scottish Natural Heritage will be taking forward this work while the review is under way."

It is likely the new boundary will resemble that proposed unsuccessfully by John Swinney in September 2006 in a member's bill. It would include the Forest of Atholl, and the community of Blair Atholl, the Beinn Udlamain mountain group to the west of the A9, an area around the A93 including Glas Tulaichean and the Spittal of Glenshee - but exclude the village of Kirkmichael.

On the question of new national parks, Mr Russell said: "First and foremost, national parks should be about local people. I am a passionate supporter of community-led initiatives and, while there are no resources available within existing spending plans for more parks, I would listen to other communities who put forward proposals for national park status.

"The North Harris Trust is one group which believes national park status would benefit the island economically, socially and culturally."

As Mr Russell was speaking, every household on Harris was receiving a letter from the community-led North Harris Trust, asking the 1900 residents whether they would support Harris joining the national park ranks.

Last night, the trust said: "After debate within the trust at the end of last year, it was unanimously agreed that there is merit in exploring the feasibility of North Harris being designated as a national park.

"Further thoughts were that other areas of Harris might wish to be partners in the process. The letter has been sent to every household on the electoral register."

The trust stressed it was not proposing a park at this stage, as had been suggested by the likes of the Ramblers' Association. Both developments were warmly welcomed by Ramblers Scotland.

Last night, Harris councillor Morag Munro, one of the leading opponents of the Harris superquarry proposals several years ago, said: "I really think everybody has an open mind on the proposal at this stage. I certainly am in favour of us taking this first step."

Western Isles SNP MSP, Alasdair Allan, also welcomed the development. He said: "I am pleased that this letter gives the initiative firmly to the people of Harris themselves."