Medals belonging to an SAS soldier who took part in the storming of the Iranian embassy will go on sale later this month.

Sergeant Tommy Palmer was awarded the Queen’s Gallantry Medal for his part in overcoming the terrorists on May 5, 1980. It will be sold alongside others awarded for his service in Northern Ireland, Dhofar and the Falklands, in a lot expected to fetch up to £120,000.

At one point during the embassy operation Sgt Palmer’s machine-gun jammed. When one of the terrorists shot at him and missed, Sgt Palmer chased him down and shot him with his handgun.

The Bonhams sale in central London on September 29 will also feature medals, logbooks and a damaged flying helmet belonging to a World War II pilot who twice survived being shot down.

The 10 medals, including a Distinguished Service Order and Distinguished Flying Cross, belonged to Group Captain Arthur Donaldson and have an estimated sale price of up to £20,000.

Capt. Donaldson went on to train Spitfire pilots in a manoeuvre which saw them dive from 8,000 to 2,000 feet.

John Millinsted, specialist at Bonhams’ medals department, said: “While with auctions you never know what will come through the door to be offered for sale, this year has been outstanding in the quality of the medals I have been privileged to put up for auction at Bonhams.”