Conservationists on Tuesday urged Thailand to end its legal trade in ivory to help curb the slaughter of African elephants by poachers cashing in on their highly-prized tusks.

While it is illegal to sell tusks from African elephants in Thailand, ivory from their Thai cousins can be traded -- a loophole allowing criminal networks to launder their wares through the kingdom, according to the WWF.

"The only way to prevent Thailand from contributing to elephant poaching is to ban all ivory sales," said Janpai Ongsiriwittaya, of WWF-Thailand.

"Today the biggest victims are African elephants, but Thailand's elephants could be next," Janpai added, urging Thai Prime Minister Yingluck Shinawatra to ban the ivory trade to protect the "iconic animals".

Demand for ivory is high in Thailand, where some wealthy people hang tusks on their walls as status symbols and the tradition of ivory carving is popular with tourists and collectors.

WWF says black marketeers routinely smuggle ivory from African elephants -- considered a "vulnerable" species -- into the kingdom and pass it off as coming from the Asian pachyderm, fuelling the poaching crisis.

"Many foreign tourists would be horrified to learn that ivory trinkets on display next to silks in Thai shops may come from elephants massacred in Africa," said Elisabeth McLellan, manager of WWF's Global Species Programme.

"It is illegal to bring ivory back home and it should no longer be on sale in Thailand."

The international trade in elephant ivory, with rare exceptions, has been outlawed since 1989 after elephant populations in Africa dropped from millions in the mid-20th century to some 600,000 by the end of the 1980s.

But poaching is at record levels in Africa, prompting Kenya's prime minister last week to appeal for international help to handle the escalating problem.

The appeal came after a family of 11 elephants were slaughtered in a national park in southeast Kenya -- which says it lost at least 360 elephants last year, an increase from the 289 killed in 2011.

A haul of more than a tonne of ivory worth about $1.4 million was found in Hong Kong two weeks ago in a shipment from Kenya.