The kingdom of Swaziland has made a surprise proposal to legalise the trade in rhino horn in order to pay for anti-poaching measures.

In a leaked document addressed to the Convention on International Trade in Endangered Species (Cites), Swaziland’s anti-poaching body said it wanted to sell the country’s 330kg stockpile of horn collected from naturally deceased animals and confiscated from poachers.

It said the sale to the traditional medicine markets of the far east would generate $9.9m, which would be used to protect the tiny landlocked country’s 73 white rhinos from poaching.

Swaziland proposed to sell a further 20kg each year, raising $600,000, by harvesting horn from living herds. Rhino horns regrow after being cut.

The Cites Management Authority of Swaziland, which made the proposal, said the 39-year-old ban on trading rhino horn had failed. It cited the poaching crisis in neighbouring South Africa, where 1,175 rhinos were killed in 2015.

“At present 100% of the proceeds from the sale of rhino horn are taken by criminals, while rhino custodians pay 100% of the costs of rhino protection and production yet they desperately need funds to cover these costs,” said the authority.

Contacts directly involved in the drafting told the Guardian that they had formally lodged the proposal with Cites. It will now be formally discussed and voted on at the Cites Conference of Parties in Johannesburg in September. The bid is likely to fail, because the majority of parties have little appetite for a legalised trade, preferring to focus on dampening demand in the Asia.

The wildlife trade watchdog Traffic said it had been completely surprised by the move and said there were major legal hurdles to its implementation. Namely, even if the country legalised the sale of its own horns, it would be illegal for anyone to buy it.

“There is still significant uncertainty as to how existing markets would be affected by any legal trade in terms of supply–demand dynamics. Such a sale might well stimulate further illegal trade and thus compound the ongoing poaching crisis,” said a spokesperson.

While it is unlikely to bring about a legal trade, Swaziland’s proposal ensures the issue will be prominently discussed at the biggest global talks on the illegal wildlife trade.

“Demand reduction and education, cited as new measures to be tried, are not new at all ... these have not been effective,” said the proposal.

The document said the move had been precipitated by the withdrawal of an expected proposal by South Africa and claimed there was near consensus about this issue at a recent meeting of Southern African Development Community (SADC). Of the 12 countries, only Botswana disagreed.

Rhino horn is a highly lucrative, illicitly traded commodity in China and Vietnam where it is considered to have medicinal properties. In fact it has none.