LONDON (Guardian) - A British airport has declared a Marmite amnesty after the popular savoury spread was found to be the number one branded food item confiscated from passengers' hand luggage.

In an unusual move, London City airport is offering travellers the chance to swop any jars of Marmite exceeding the permitted 100ml size for a travel-friendly 70g miniature.

The amnesty was in force until late on Monday but could be repeated if deemed successful.

The airport said Marmite is the most regularly seized branded food product at its security gates, and in the top 10 overall for confiscated items.

The most commonly confiscated item is snow globes, followed by jams and spreads and toiletries.

It is using the promotion to highlight what it said would be its busiest day of the year so far, as holidaymakers stuffed their cabin bags with food and drink that they could not bear to be without while away.

A study revealed that about one in eight people in Britain has had to give up an item packed in hand luggage because it did not meet aviation or immigration rules.