CAMPAIGNERS fighting to save the Black Watch have made an emotional appeal to the Prince of Wales to intervene as the battle to save the regiment steps up a gear.

In a letter to the prince, who is colonel-in-chief of the regiment, the campaigners invoke the spirit of his late grandmother, pointing out that the Queen Mother always stood by the regiment when it came to defence cuts.

They also cite the regiment's performance in Iraq, when the Black Watch fought in the battle for Basra.

The way is open for the prince to apply diplomatic pressure on the defence secretary and military top brass ahead of the final decision on proposed defence cuts later this year.

Last night Nicholas Soames, shadow defence secretary and a confidant of Prince Charles, said: ''If I were a member of the Black Watch I would be outraged. The regiment has soldiers in Iraq and they are now being told they face being disbanded.

''It's an outrageous proposition. The Scots have made a tremendous contribution to the British army and given generations of distinguished service to the Crown.''

The Conservative MP for Mid Sussex, who declined to comment directly on the appeal to the prince, described as ''madness'' the government plan to cut troop numbers and claimed that the axing of historic infantry regiments showed that New Labour had no feeling for the community spirit that local regiments instil.

''New Labour don't mind about this; they are not interested in it. The ethos of service and loyalty is completely alien to them,'' he added.

A spokesman for the prince declined to comment last night and Charles, who is colonel-in-chief of eight other regiments, may never do so publicly.

A letter to the prince has been posted on the Save the Black Watch website with campaigners hoping hundreds of supporters will sign it to urge him to add his voice to their cause. Already, an online petition to Tony Blair has raised nearly 3000 signatures from as far afield as America, Australia, Brazil and Iraq - where the regiment is currently serving.

The dramatic move by campaigners to involve the prince significantly raises the stakes in their efforts to save the Black Watch and comes as the fate of all six of Scotland's infantry regiments draws near.

The regimental colonels are due to meet to discuss how to wield the Whitehall axe at a special meeting on September 13. Two days later, Geoff Hoon, defence secretary, is to be cross-examined on the subject by MPs.

Charles became the Black Watch's colonel-in-chief last year, taking over the role held for 60 years by his beloved grandmother following her death in March 2002. Such was her devotion to the regiment that 80 pipers and drummers from the Black Watch helped lead the procession at her funeral.

Andy Duncan, a former Black Watch private from Whitehills near Banff, who is behind the regimental campaign, said: ''If Charles did come on board and has a lot to say on the matter, then that would apply great pressure to the government.

''We know he does a lot of work for other groups and charities and we're hoping he will do some work for his own regiment.''

Jeff Duncan, who is the organiser behind the broader Save the Scottish Regiments campaign, said he was sure the Queen Mother would wish her grandson to take up the fight and give the survival of her beloved regiment as much importance as she did.

The 44-year-old Dundonian businessman, who is a former RAF serviceman but whose grandfather served in the Black Watch, revealed how consideration was also being given to writing to other members of the royal family.

Each of the six Scottish infantry regiments has a royal colonel-in-chief: the Queen (Argyll and Sutherland Highlanders); the Princess Royal (the Royal Scots); Prince Philip (the Highlanders); Prince Andrew (the Royal Highland Fusiliers) and Princess Alice (the King's Own Scottish Borderers).

Prince Charles is also deputy colonel-in-chief of the Highlanders.

He last visited the Black Watch in April when he toured its regimental headquarters in Perth after he attended Balhousie Castle for the opening of the memorial gates dedicated to the Queen Mother.

At the time he said: ''For me, it is an enormous privilege to be able to open these gates in memory of my darling grandmother. I was so proud to be asked to become colonel-in-chief of this remarkable regiment, the Black Watch.''

Last night, a spokeswoman at St James's Palace stressed that the prince was proud to be colonel-in-chief of the Black Watch and took his role very seriously but declined to drawn on the axing of the regiment. ''We would not comment on that,'' she said.

Serving Scottish soldiers are currently being asked in an official questionnaire whether they support one of two options: to create a new Highland and a new Lowland regiment, or to have just one super-regiment for Scotland. Brigadier Gary Barnett, the Black Watch's previous colonel, described the plan to cut numbers as well as historic regiments as ''nonsensical, immoral and wrong''.

''There is no doubt in my mind that the vast majority wish to see the thing stay as it is and don't want to change a system that works,'' he said.

Brigadier Barnett said the troops currently serving in Iraq would feel let down by the MoD's decision to end hundreds of years of tradition.

Rachel Squire, a defence committee member and Labour MP for Dunfermline West, said yesterday: ''I'm very keen that we have a full investigation of all the aspects of the defence statement. We would need a lot of time and evidence sessions to do that.''

Ms Squire, in whose constituency the Black Watch recruit, is one of few Labour MPs to back the campaign publicly.

She feels that unless Britain is prepared to reduce its global commitments, then ''we need to maintain our forces at the current level''.

The letter to the Prince of wales

WE wish to make this appeal to your Royal Highness in the hope that we can save our regiment from the savage defence cuts proposed by the defence secretary, Geoff Hoon, and his chief of general staff, General Sir Michael Jackson.

As colonel-in-chief of this very famous regiment I am sure you understand how important it is to save this regiment for historical and operational reasons as we have seen just lately when the regiment found itself back in Iraq when only a year ago it exemplified itself in the battle for Basra.

This regiment was always loved by your grandmother, the late and much loved Queen Mother, who always stood by her regiment when defence cuts were looming. The Queen Mother always wore the Black Watch badge of honour with pride, just as you do. The Black Watch have always been there for Queen and country and to protect us all in time of need, now the Black Watch need us to help it in its time of need, like the ''Watch'' with all its courage we must support the regiment with the courage to take on the politicians and the generals and show a fortitude that would make the defence secretary see we are willing to fight for our regiment, we want to say to him, ''hands off the BLACK WATCH''.

Wha daer meddle wi' us do so at your peril Mr Hoon!

We are proud of our regiment, fathers, sons and grandfathers who served in the Black Watch, they were committed to the regiment because it was and still is their local regiment, they are proud of the traditions and the history of the regiment.

The local connections which are vital to recruitment will be lost forever if we lose our regiment, so please Prince Charles we urge you to step in and help us with all your authority as colonel-in-chief to help us save this famous fighting regiment who are committed to fighting terrorism in one hand and also doing good humanitarian work with the other.

We need all the Scottish regiments now, and more than anything we need the Black Watch since the world is a very unstable place nowadays.