Smaller breeders as well as commercial breeders will have to meet a “strict welfare criteria” and those who sell pets on the internet will be subject to the same licensing regulations.
Breeders who break the rules face an unlimited fine and up to six months in prison. Ms Leadsom said: “Everyone who owns a pet or is looking to introduce one into their life will want to know that the animal has had the very best start to life.
“Yet for thousands of puppies born each year to irresponsible breeders, from smaller operations to larger puppy farms, their first weeks are spent in cramped and squalid conditions without the care and attention they need.
“That is why we are cracking down on the worst offenders by strengthening the dog breeding licence and giving councils the power they need to take action.”
Battersea Dogs & Cats Home praised the plans as a “welcome first step”. The charity’s chief executive Claire Horton said: “It’s high time we put a stop to the many undercover backstreet breeders and large-scale puppy farmers that profit from their cruel treatment of these animals.
“No puppy should start its life in cramped, squalid surroundings, before being torn away from their mother at a few weeks old.
“So many owners buying their new pet would be horrified to know that this was indeed the case.”
Kennel Club secretary Caroline Kisko said: “We are pleased that Defra will be taking forward proposals to ban the sale of puppies under the age of eight weeks by commercial third parties.
“We have called for a ban on third party sales, and refuse to register puppies being sold to third parties, but this new rule is a step in the right direction.
“We also welcome the requirement for pet sellers to provide written information about the animals they sell and for those who sell pets online to display their licence number.”