THERESA MAY has made more U-turns than the clown’s car in Billy Smart’s circus. And she has dropped promised policies and buried others too.

So many, in fact, that you might have missed her abandonment of Tory promises to ban the sale of ivory in Britain. One person who hasn’t is the second-in-line heir to the throne, William Windsor.

Along with conservation groups, environmental campaigners, politicians and celebrities, he has said that the reversal in policy would lead to the illegal killing of thousands of elephants, and urged the government to implement a total ban on all ivory trade.

The Conservative manifesto at the last general election vowed that a Tory government, if elected, would press for a total ban on ivory sales. After the election, May and Environment Secretary Andrea Leadsom seemed to be ready to put the policy into law.

Then, as with so many Tory promises from May and her gang, it simply disappeared. There is no mention of the ban in the Tory 2017 manifesto.

Sneakily, May, Leadsom and the Tories have decided to abandon their previous commitment to introducing a total ban on the ivory trade in Britain. They have done it after heavy lobbying from wealthy London antiques traders who have been pressing the Prime Minister hard to drop the ban.

The most powerful antique traders association is the British Antique Dealers’ Association. It’s president is Lady Victoria Borwick, Tory MP for Kensington and long-term pal and ally of May.

On average, an elephant is killed every 15 minutes for its ivory and their population has fallen by almost a third in Africa since 2007. As I have warned in these pages before, the African elephant population is hurtling towards extinction in the wild.

By far the biggest threat comes from poaching for ivory for the illegal trade in objects and artefacts collected by those with far more money than either good taste or environmental responsibility.

Interestingly, this ivory policy reversal puts May and her Tories in direct conflict with Windsor, who has been a vocal supporter of a total ban on ivory sales. The Prince is patron of Tusk, one of the charities that have linked ivory sales in Britain to the slaughter of 30,000 elephants a year in Africa alone.

Will we see the Duke of Cambridge campaigning for Labour, which has pledged to introduce the total ban he has been lobbying for?

Environment Secretary Andrea Leadsom is under increasing pressure to make good on the Tory manifesto commitment to ban Britain’s ivory trade after China announced it would close down its domestic ivory market.

At the Convention on the International Trade in Endangered Species (Cites) meeting in Johannesburg last year, 182 nations gathered and agreed for the first time in its history that national ivory markets should be closed rather than regulated.

Many countries, including Britain, have allowed antique and other ivory pieces to be bought and sold. But the Cites nations agreed unanimously that every state should take all necessary steps to close their domestic markets for commercial trade in raw and worked ivory as a matter of urgency.

“There is no legal market that doesn’t contribute to the illegal trade,” said Susan Lieberman of the Wildlife Conservation Society.

Conservation organisations, including a charity championed by Windsor, say that by allowing the trade to continue Britain is fuelling the annual slaughter of thousands of elephants. A recent study suggested that this country is now the third-largest supplier of illegal ivory items to the US. The legal ivory trade here provides cover to criminals to launder illegal ivory through Britain.

In theory, it is only legal to sell items made from elephant ivory if it can be proved to have been manufactured before June 1 1947. But more modern poached ivory can be distressed to look older and circumvent regulations. Provenance proving an ivory artefact is old and therefore legal can be all too easily forged.

Ivory can come from many animals as well as elephants — from the hippopotamus, walrus, some whales, hogs and boars and much still comes from the long extinct woolly mammoth.

Mammoth ivory is found in melting glaciers, mostly in Siberia, and trade in it is legal. Tons of it was imported in the past and it was so common that many Victorian and Edwardian pianos had mammoth keys.

Today, many items made from recently poached elephant ivory change hands for huge amounts of money in London’s expensive antique emporiums and prestigious auction houses.

It is exported legally and illegally to the US and China, both of whom have many ivory collectors prepared to buy new ivory items despite the legal ban.

Boris Johnson, William Hague and former Defra secretary Owen Paterson all support a total ban on the sale of any ivory, while the Labour Party introduced a pledge for a total ban on ivory trading in its 2017 manifesto.

There are many good reasons to vote Labour in next week’s election and one of them is to save the biggest land animal on the face of the Earth from extinction by poaching.

The other is that perhaps the man who would be king thinks you should.