A South African court on Friday froze a donation of military helicopters to Zimbabwe's army after the planned transfer sparked an outcry ahead of elections in the neighbouring country.

"An urgent interim court order was awarded... to prevent delivery of Alouette III Air Force helicopters by the South African National Defence Force to the Zimbabwean army," said the AfriForum lobby group, which brought the matter before the court.

The order was handed down late Friday after the group sought an urgent bid to block the move, following news that the South African defence department planned to donate spares and frames of its retired chopper fleet to Zimbabwe.

"All indications are that the Zimbabwean army is enhancing its visibility, mobility and presence across Zimbabwe in anticipation of the national elections that are scheduled to take place later this year," said AfriForum in a statement.

The interim order is valid until a main court application is finalised by February 19.

The materiel is part of the French-developed Alouette III helicopter and is intended for the Zimbabwean Defence Force (ZDF), which backed President Robert Mugabe in previous bloody elections.

"We are sending spare parts of the helicopter that has been phased out and the frames," said Siphiwe Dlamini, spokesman for the Department of Defence.

The size of the delivery and the timeframe could not be confirmed, but Dlamini insisted assembled helicopters will not be sent across the border.

"These things are not assembled -- they are spare parts and frames. There is nothing like a fully-fledged helicopter."

South Africa's defence department said the equipment was part of a decision that dated back to 1997. The helicopters were used, including by apartheid forces, from the early 1960s until 2007 when they were retired.

Zimbabwe's polls this year -- though no date has yet been set -- will replace a shaky compromise government between Mugabe and long-time foe Morgan Tsvangirai, forced after 2008 election violence killed around 200 people and caused an economic meltdown.

South Africa's main opposition Democratic Alliance accused President Jacob Zuma's government of bordering on "state-sponsored smuggling" to help Zimbabwe's military get around international arms embargoes.

The equipment is set to be shifted without clearance under arms export regulations, which stipulate no trade with aggressive or repressive states, as it reportedly had been stripped of all weapons systems.

"And yet the helicopters and spare parts are clearly destined for use by the ZDF, which is practically an extension of President Robert Mugabes ZANU-PF terror machine in Zimbabwe," said shadow defence minister David Maynier.

United Nations sanctions against Zimbabwe, including an arms embargo, were vetoed in 2008.

But the European Union and the United States imposed a visa ban and assets freeze on Mugabe and top officials, as well as an arms embargo on the country following disputed presidential polls in 2002.

Mugabe retained control of the army and police under the power-sharing deal and both are seen as highly loyal to the 88-year-old veteran leader.

The military was accused of widespread abuses during the 2008 elections and of killing 200 informal miners in the same year when clearing eastern diamond fields.

AfriForum said it had written to the acting French ambassador of the potential risk of the EU arms embargo being breached.

The Stockholm International Peace Research Institute (SIPRI) think-tank said the details were unclear without access to the original contracts between France and South Africa.

If an end-user pact was signed requiring France to give the nod to any future re-export, then this would be violated due to the EU embargo. However, the decades-old deal was inked when such agreements were not common.

"In other words, it is fully possible that the helicopters were supplied to SA from France without any conditions about re-export," said Pieter Wezeman, senior researcher in the group's arms transfers programme.