Cooks are to be able to buy "tearless" onions for the first time when they go on sale in the UK from next week.

The Sunion onion is perfect for those with sensitive eyes as well as cooking in the kitchen with children, British supermarket chain Waitrose has said.

Their mild flavour makes them perfect for use in cooking while they can also be used raw in a salad, the firm added.

The onions are the invention of Rick Watson, a plant breeder working for the German chemical company BASF.

He began working on the innovation in the late 1980s, using natural techniques rather than genetic modification to create the unique variety.

The brand said it took more than 30 years of breeding less pungent varieties of onion to find a variety where the vapours released on chopping are not powerful enough to bring tears to the eye.

A three-pack of Sunions will cost £1.50, 30p more than a four-pack of Waitrose's own-brand onions.

Sunions said its onions are not a genetically modified product and were grown through an all-natural cross-breeding programme.

It said volatile compounds in onions are responsible for the tears and pungent flavour, and the amounts of those compounds in other onions remain the same or increase over time. In Sunions, these compounds do the opposite and decrease to create a tearless, sweet and mild onion.

Sunions are already on sale in America but have not been universally well-received.

A 2018 review in the Washington Post said they were very sweet - "sweet enough that you could sit there and eat them like popcorn" - and barely had any scent.

Another journalist who tried them there said they were "almost flavourless".