Botswana on Wednesday lifted its ban on elephant hunting, saying the population had increased and farmers' livelihoods were being impacted, in a move set to trigger outrage from conservationists.

A prohibition on elephant hunting was introduced in the southern African country in 2014 by then-president Ian Khama, a keen environmentalist.

But lawmakers from the ruling Botswana Democratic Party (BDP) have been lobbying to overturn the ban, saying numbers have become unmanageably large in some areas.

President Mokgweetsi Masisi took over from Khama last year and a public review began five months later, with reports suggesting growing political friction between Masisi and his predecessor.

"Botswana has taken a decision to lift the hunting suspension," the environment ministry said in a statement.

It said a cabinet committee review that found that "the number and high levels of human-elephant conflict and the consequent impact on livelihoods was increasing".

"The general consensus from those consulted was that the hunting ban should be lifted," it added, vowing that hunting would be re-started "in an orderly and ethical manner".

Landlocked Botswana has the largest elephant population in Africa, with more than 135,000 roaming freely in its unfenced parks and wide open spaces.

Some experts say the number of elephants in the country, renowned as a luxury safari destination, has almost tripled over the last 30 years, and that the population could now be over 160,000.

Crops destroyed

Farmers struggle to keep elephants out of their fields where they eat crops and can kill people.

Lifting the hunting ban could be a popular move with rural voters ahead of an election due in October.

Many of Botswana's elephants roam across borders into Namibia, Zambia and Zimbabwe.

All four countries have called for a global ban on elephant ivory trade to be relaxed due to the growing number of the animals in some regions.

"We cannot continue to be spectators while others debate and take decisions about our elephants," Masisi told a meeting of the countries' presidents this month in Botswana.

"Conflict between elephants and people is on the rise as the demand for land, for agriculture and settlements is growing," he said.

While elephant numbers have increased in some areas, over the past decade, the population of elephants across Africa has fallen by about 111,000 to 415,000, largely due to poaching for ivory, according to the (IUCN).

Zimbabwe said this month it had sold nearly 100 elephants to China and Dubai for a total price of US$2.7 million over six years due to overpopulation.

Botswana last year rejected claims by a leading conservation charity that there had been a surge of elephant poaching.