But the Army insisted that the name of Operation Helvetic - which replaces Operation Banner at midnight - is purely coincidental.

The often enigmatic names for military operations are chosen randomly, the military says.

But Army sources say they were struck by the coincidence.

The Helvetic Society was formed in 1762 to promote "friendship and love, association and harmony" among the Swiss confederates. Both Protestant and Catholic scholars and thinkers joined.

A Helvitic Republic also ruled most of what is modern Switzerland at the start of the 19th century, but discord resurfaced: a civil war between Protestants and Catholics took place in the middle of that century.

The root of the name comes from the Helvetii, a Celtic tribe that was largely destroyed by Julius Caesar's Roman legions.