HUNDREDS of Scottish soldiers face an uncertain future today as the UK Government announces the 131-year-old Argyll and Sutherland Highlanders is to be cut to 100 men with the role of guarding Edinburgh Castle, the Palace of Holyroodhouse and Balmoral.

Ministry of Defence sources insisted the new role for the 460-strong battalion of 5 Scots was positive after feverish speculation the Royal Regiment of Scotland would lose one if not two of its five battalions in the latest round of Army cuts.

However, the Whitehall department is bracing itself for a backlash from English MPs, who believe the Scottish independence referendum means battalions north of the Border are taking less of a hit than those south of the Border.

One Labour backbencher said: "The political hand of No 10 is all over this."

Some four or five battalions in English regiments are due to be axed as the Government seeks to reduce the regular British Army force from 102,000 to 82,000. Units like the Yorkshire regiment, the Royal Welsh, the Mercians and the Royal Fusiliers look set to be affected.

Already, one Conservative backbencher has claimed: "There is a great deal of resentment among Army officers in the way that excellently recruited English battalions are going to the wall when badly recruited Scottish battalions are staying."

Colonel Bob Stewart, the former commander of UK forces in Bosnia and now a Tory MP, recently warned the Scottish division should take its fair share of cuts, insisting it must not be protected for political reasons.

Recent figures show the Highlanders battalion has the worst recruitment shortfall in Scotland of 24% while the Argylls have one of 16%.

Last night, a senior Whitehall source told The Herald: "People will be quite surprised and impressed by this positive move given they were expecting a Scottish battalion to be scrapped."

He said the transformation of 5 Scots into a public duties company – the only change to Scottish units expected in Defence Secretary Philip Hammond's Commons statement today – would "raise the profile" of the Royal Regiment of Scotland as the only other place in the UK to have one was London, where sentries are posted at Buckingham Palace, the Tower of London and St James's Palace.

In Scotland, the Argylls will be posted at Edinburgh Castle, the Palace of Holyroodhouse and at Balmoral Castle when the Queen is in residence. Their company barracks in Canterbury will be maintained.

The defence source explained those 100 or so troops, who will be involved in the public duties company, would be deployed on a rotational basis, meaning that from time to time they would still be used on operations.

Of the remaining 350 personnel, some would be redeployed to sister battalions, possibly elsewhere in the Royal Regiment of Scotland, but others could face redundancy – the source would not elaborate.

Last night, Angus Robertson, the SNP's defence spokesman, said: "The Coalition Government has acknowledged Scotland's armed forces personnel have been disproportionately cut in recent years. This involves a 27% cut in Scotland compared to only 11% in the rest of the UK. Scotland has paid more than its fair share in personnel cuts and means its infantry is now smaller than that of the Irish Republic."

He added: "We await confirmation that the Tories are reneging on their commitment to restore fully the six Scottish infantry regiments."

The MoD was keen to stress that retaining the Argylls, albeit in a reduced capacity, would maintain the "golden thread" of military history, including the unit's historic cap badge.

The 5 Scots battalion was formed in 1881 from two Highland regiments, the 91st Argyllshire Highlanders and the 93rd Sutherland Highlanders.