Captain Doug Beattie claims Collins' address to the Ist Batallion of the Royal Irish Regiment in March 2003, contained "a little too much reality" by reminding soldiers they could be killed in battle.

The speech by Col Collins - which received special praise from the Prince of Wales and reportedly hangs in the Oval Office of US president George Bush - urged troops to to be "ferocious in battle" but "magnanimous in victory" and "tread lightly" on Iraq's ancient landscape.

In his memoir, Captain Beattie claims he was forced to rouse his men in the immediate aftermath of his commanding officer's words.

The Portadown man recalls using a "string of barely separated profanities" to kick his men "back into life".

Writing in his book - An Ordinary Soldier - Captain Beattie said: "I knew I had a problem. He (Collins) had left the men somewhere they shouldn't have been: thinking about home, wondering if they would ever return there again, fearful of the dangers that faced them in the hours, days and weeks ahead.

"The speech had been rousing, but also sobering - it pulled no punches, the message was stark.

"He had told the men they would not all be coming back, and now it seemed the majority of them were asking if they would be amongst the fallen. They had to be snapped out of it," he added.

Captain Beattie - who was awarded the Military Cross for his role in leading Afghan troops to retaking the town of Garmsir - will leave the Army in January after 27 years service.