Trading ivory from a hippo, walrus, narwhal, killer whale and sperm whale will soon be illegal, the government says.
The Ivory Act of 2018 came into force last June to protect elephants and now it will be extended to cover those five other species.
Naturalist and TV presenter Steve Backshall said: “This is an important moment in the conservation of these iconic species.
“There is widespread public support for the ivory ban and today by extending it further we are sending a clear message that there is no place in the UK for this vile trade.”
The change will take effect “in due course” depending on the availability of parliamentary time, with punishment for breaching the act being an unlimited fine or up to five years in jail.
Biodiversity minister Trudy Harrison said: “This is a pivotal moment in delivering one of our key manifesto commitments on international conservation.
“The Ivory Act is one of the toughest bans of its kind in the world and by extending greater legal protections to five more species, we are sending a clear message the commercial trade of ivory is totally unacceptable.
“The UK has long led the way in conservation and our ban shows continued global leadership in doing all we can to protect the world’s most endangered species.”
Hippos are the most at risk of ivory exploitation after elephants, according to the Department for Environment, Food and Rural Affairs.
The International Union for the Conservation of Nature’s red list classes hippos as vulnerable, along with the walrus and sperm whale, all of them being threatened by pollution, shipping lanes, climate change and human conflict.
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‘A good day for conservation’
Frances Goodrum, head of campaigns and programmes at the International Fund for Animal Welfare, said early indications are that the ban is having “a significant impact” on the trade in elephant ivory.
“Yet other species are still poached globally to meet an unnecessary demand for luxury ivory products, including the hippopotamus, walrus, narwhal, sperm whale and killer whale.
“We welcome Defra’s decision to extend this powerful legislation, which will go a long way in cracking down on a damaging trade.
“Today is a good day for conservation and a step change towards international commitments to safeguard our natural world.”