American bully XLs, which could be banned by the Government and have been described as a "lethal danger" by Suella Braverman, are on sale for as a little as £250.

The home secretary announced she is seeking urgent advice on outlawing the dogs after an "appalling" attack on an 11-year-old girl and two men in Birmingham last weekend.

"This is appalling. The American XL bully is a clear and lethal danger to our communities, particularly to children," Braverman wrote on social media.

"We can’t go on like this. I have commissioned urgent advice on banning them."

Bully XLs have killed in the UK, with 10-year-old Jack Lis dying after being mauled by one of the dogs in at a friend's house in Caerphilly, South Wales in 2021.

Research by this newspaper has found that bully XL puppies, which Conservative MP John Hayes described as being "bred to kill", are being sold in Hertfordshire for low prices.

One listing has an 11-week-old puppy in Letchworth being sold for just £250, while another in Royston has a litter of six nine-week-old XLs listed for £750 each.

In Brookmans Park, 13-week-old puppies from a large litter are being sold at just £450 each, with another being sold in Markyate for £1,000.

Another, this time sold in Hitchin for £1,300, claims the dog has been around children, despite a number of bully XL victims being children.

The Department for Environment, Food and Rural Affairs (Defra), has concerns over the feasibility of adding the American bully XL to the banned list, as the dog is not recognised as a specific breed by the Kennel Club.

A Defra spokesperson told the Guardian: "We take dog attacks and anti-social behaviour very seriously and are making sure the full force of the law is being applied.

"This can range from lower-level community protection notices – which require dog owners to take appropriate action to address behaviour – to more serious offences under the Dangerous Dogs Act, where people can be put in prison for up to 14 years, be disqualified from ownership or result in dangerous dogs being euthanised."

In the UK, the pit bull terrier, Japanese tosa, dogo Argentino and fila Brasileiro are the only banned breeds.