However, if someone impedes their progress, the soldier would normally shout "Make way for the Queen's Guard."
In a statement the Ministry of Defence said: "The Household Division is proud to guard Her Majesty and honoured that people come from around the world to watch our ceremonial spectacle.
"The ropes are there to protect both the public and our soldiers; please stay behind them."
The Queen's Guard, manned by fully-trained, serving soldiers, have more than 350 years of history and have defended monarchs since Charles II took the throne after the English Restoration in 1660.
The Guards consist of five infantry regiments — the Grenadier, Coldstream, Scots, Irish and Welsh Guards — and two regiments of the Household Cavalry — the Life Guards and Blues and Royals.
In 2015, a soldier turned his rifle on a tourist who grabbed him outside Windsor Castle.
To giggles from his friends, the Asian man marched alongside the serviceman and placed his hand on the soldier's shoulder.
But the soldier suddenly spun round and pointed his weapon at the tourist, shouting: "Get back from the Queen's Guard!"
And in an incident at St James' Palace last year, it seems a guard simply had enough with a man dancing and singing in front of him and his colleague.
The guard stepped forward from his post and bellowed "Halt! Get yourself away!"
The tourist turned around, stunned, before scampering away as the Scotsman kept shouting at him to turn the camera off.