Image copyright Getty Images Image caption Elephants in Botswana, which has more of the animals than any other country in Africa

The UN body that oversees trade in endangered species, says it will oppose efforts to increase global protection for elephants.

The Convention on International Trade in Endangered Species, known as CITES, is meeting this weekend with many African countries are pushing for stronger safeguards for elephants.

It is estimated that around 20,000 are killed each year for their tusks.

But CITES says that tougher rules could backfire and boost the trade in ivory.

Every three years, teams of officials from all the member states meet for the CITES Conference of the Parties (COP).

This is the major decision making body for the UN organisation that regulates trade in endangered species of flora and fauna for 183 members.

CITES works by classifying these species into one of three appendices with different levels of protection and different rules on trade.

This year's meeting of CITES in Johannesburg is considering dozens of proposals on regulating the trade in everything from tiny frogs to sharks, to trees and flowers as well as the more high profile threatened species such as rhinos, lions and tigers.

But it is the question of how to deal with the current poaching crisis in elephants that is top of the bill at this the 17th COP in the Convention's 43-year history.

War on elephants - Alastair Leithead, Africa correspondent

Image caption The growing demand for ivory in Asian markets means the illegal trade continues to threaten the future of elephants in Africa

Every year in Africa between 30,000 and 40,000 elephants are poached for their ivory, and it's thought there are only 400,000 left.

Even accounting for the newborns, this rate of killing calls into question whether these amazing creatures will still be around in a generation, especially as Africa's ever-increasing population is reducing the space for them.

Organised crime runs the ivory industry.

"Corruption is probably the single biggest cause of the increase in elephant poaching," says Esmond Bradley Martin, who has spent decades talking to traders and traffickers and investigating smuggling routes around the world.

Extract from The War on Elephants; article on how the very existence of Africa's elephants is threatened by poachers

More from Alastair:

Why elephants are seeking refuge in Botswana

Shocking reduction in Africa's elephant numbers

At present, all African elephants, except those in South Africa, Zimbabwe, Botswana and Namibia, are listed in CITES Appendix I, meaning that any commercial trade in specimens or parts is banned.

In the southern African states, the animals are listed as Appendix II, meaning that a trade in hunting trophies for non-commercial purposes is allowed, as is a trade in live animals to "appropriate and acceptable destinations." However their ivory is considered to be in Appendix I and a global ban on legal trade remains in force.

But a coalition of 29 other African countries is pressing for a tightening of the regulations proposing that all elephants on the Continent be listed in Appendix I.

Image copyright Getty Images Image caption The number of elephants in some countries in Africa has halved in the past seven years

"The evidence for keeping these elephants on Appendix II is entirely lacking," said Prof Phyllis Lee from the University of Stirling, who is a participant in the Kenyan Elephant Forum, which is pushing for greater protection.

"They have suffered a decline, it is projected to continue and the ivory from those populations is present in the trade, all of those are significant grounds for up-listing to Appendix I under CITES regulations."

But CITES disagrees and is recommending that the proposals for up-listing be thrown out. They worry that if the resolution is passed, the extra restrictions could see some countries break away from the Convention and resume an unregulated trade.

"There are 90 days for any country to enter a reservation against that decision, that listing to Appendix I," CITES executive secretary John Scanlon, told BBC News.

"If they enter a reservation, the Convention doesn't apply to them for that particular species, and if other countries also enter a reservation they can trade with each other outside of the scope of the Convention. So there is a degree of risk associated with that."

African elephants facing an uncertain future

Reaching heights in excess of three metres and a mass of six tonnes, African elephants are the world's largest land animal.

The latest assessment from the IUCN (International Union for Conservation of Nature) Red List of Threatened Species lists the African elephant population as Vulnerable, suggesting that - on a continental scale - the species' numbers had been "progressively improving" since the mid-1990s.

However, in recent years, the overall numbers are in decline. Data suggests a fall in the number of "definite" elephants, from 472,661 in 2007 to 401,732 in 2013.

In some regions gripped by civil unrest, such as central Africa, elephants are under threat from ivory poachers and habitat loss. Countries like Tanzania and Mozambique have lost half their elephant populations between 2009 and 2015.

Yet in other parts of the continent, such as South Africa and Uganda, effective management programmes have seen numbers increase.

As each elephant generation is 25 years, failure to protect and conserve our biggest land animal today will have a lasting legacy on the landscape and ecology of Africa.

Conservation groups are divided on the question. Many are in favour of the up-listing, saying the lack of clear data from some southern African states makes it uncertain that the populations of these countries are thriving,

Others, such as WWF, agree with the CITES secretariat, saying that there is already a de-facto ban on ivory around the world and putting all the African elephants on the highest level of protection won't provide any clear benefits and may actually make the situation worse.

"Far from increasing the level of protection, up-listing opens up a loophole window where countries who want to trade can effectively opt out of the treaty as far as elephants are concerned," said Dr Colman O'Criodain from WWF.

"That would allow them to trade and it could spark off a trade in ivory that isn't happening right now.

"We also defend the principle of scientific criteria first and they are deemed not to be met in this case. Of course if there weren't an existing ban on ivory trade, we might feel differently but there is. It's not the most legally tidy, but it works."

Image copyright Getty Images Image caption Ivory tusks in Kenya being prepared for burning. Kenya is one of the countries seeking stronger protection for all African elephants

There is a great deal of uncertainty as to how the elephant issue will play out - neither the proposal to liberalise the market or to increase protection is likely to achieve the two-thirds majority of delegates needed to change the Convention.

There are worries that if the elephant question becomes so divisive, it may disrupt attempts to protect other, less glamorous species such as pangolins and the African Grey parrot.

However, some observers believe that the convention might rally round another proposal to end domestic sales of ivory - something that occurs for antique ivory in many countries including China and the UK and the US.

"There are a number of governments that have done it, there are a number that are doing it," said Sue Lieberman, from the Wildlife Conservation Society.

"It won't be legally binding but it will push governments to do it, and that will make a massive difference, bigger than putting them on Appendix I."

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