Bréal's Silver Cup, named after the Frenchman who had the idea of staging the marathon at the first of the modern Games, Michel Bréal, has been offered for sale for the first time by Louis' grandson – also named Spyros.

"Our family has been very proud to have the honour of looking after this important historical sporting trophy for the last 116 years and my grandfather's achievement of winning the first ever marathon, at the first modern Olympic Games will remain part of my family's heritage forever," said Louis.

"However, it is time to look to the future, not the past – I have two children, and the most important thing for me is to ensure that they are looked after as well as possible.

"It is always going to be impossible to split a cup, so I have decided that the most sensible thing to do is to offer it at auction, and use the proceeds to secure the future of my family."

The cup, which is just six inches high, will be auctioned alongside other Olympic icons at the South Kensington showroom on April 18.

A selection of eight original Olympic torches dating from 1936 through to 1996 (estimates from £700 ($1,100/€835)), as well as 26 original Olympic advertising posters dating from the first London Games in 1908 through to Tokyo in 1964 also feature in the Olympic section of the sale.

The sale as a whole comprises 179 lots and is expected to realise in excess of £700,000 ($1.1 million/€835,000).

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