South African dockers are refusing to unload a Chinese cargo ship carrying 77 tonnes of small arms destined for Zimbabwe.

The arms, including three million rounds of ammunition suitable for AK47s and 1,500 rocket-propelled grenades, were ordered by the Zimbabwean military at the time of the March 29 election – which Britain and other Western powers have accused Robert Mugabe of trying to rig.

The arms arrived at Durban, South Africa, on Wednesday aboard the Chinese-owned An Yue Jiang and must be taken by road to landlocked Zimbabwe, where the Government has been accused of arming rural militias before a possible run-off vote for the presidency. The opposition Movement for Democratic Change (MDC) has even accused Mr Mugabe's Zanu (PF) of preparing for a "war" against the people.

January Masilela, the South African Defence Secretary, said yesterday that the shipment had been approved this week by the National Conventional Arms Control Committee (NCACC), which he chairs. "This is a normal transaction between two sovereign states and we don't have to interfere," he said.

But opposition parties slammed the decision to grant the transit permit and the country's main transport union said that its members would refuse to unload the cargo.

“We do not believe it will be in the interest of the Zimbabwean people in general if South Africa is seen to be a conduit of arms and ammunition into Zimbabwe at a time when the situation could be described as quite volatile,” said Randall Howard, a spokesman for the South African Transport and Allied Workers Union (SATAWU).

“As far as we are concerned the containers will not be offloaded”.

Rafeek Shah, defence spokesman for the Democratic Alliance, the main South African opposition party, added: "The world's astonishment at President Mbeki's political defence of Robert Mugabe will likely turn into outright anger as we are now not only denying the existence of a crisis in Zimbabwe, but also actively facilitating the arming of an increasingly despotic and desperate regime."

AfriForum, a regional business lobby group, has said that it would organise protests along the shipment's route. The South African Institute of Race Relations said that if the shipment goes ahead, "South Africa's culpability in the Zimbabwe crisis would then be without question."

Meanwhile, the South African Government's decision to allow transit of the shipment was the subject of an urgent legal challenge at the Durban High Court.

Nicole Fritz, head of the Southern African Litigation Centre, told Times Online that under the 2002 National Convention on Arms Control, which the NCACC monitors, the permit should not have been granted. That law, she said, specifically prohibits the shipment of arms that will "contribute to internal repression".

In addition, allowing the arms shipment would violate South Africa's international commitments under a range of agreements including the 1996 Wassenaar Arrangement.

"This is a very clear example of a situation in which the committee will be obliged to review a permit," she said, predicting that the High Court would order a stay on the shipment.

There have been persistent reports about Chinese arms sales to Zimbabwe, although the details are hard to pin down.

Zimbabwe announced in 2006 that it had bought six fighter jets from China, adding to a fleet of six it bought the previous year in a deal believed to be based on barter – with China obtaining precious mineral raw materials needed in its economic boom.

Zimbabwean officials said that the aircraft deal also included the purchase of 100 military vehicles from China to replace existing items that were no longer operational since Western sanctions halted imports of spare parts and maintenance equipment.

China’s sales of military hardware are believed to have amounted to more than US$200 million in recent years. There have also been reports that the Chinese have sold water cannons and mobile phone bugging equipment to the security forces in Harare – although it is not clear whether or not those sales were instigated by companies operating outside the control of central government.

Mr Howard, the SATAWU spokesman, said that the An Jue Yiang was carrying 36 containers, 30 of which were equipment for the mining industry in South Africa and Botswana.

“The balance is earmarked for Zimbabwe, four of which have arms and ammunition in them and the other two military aircraft ejector seats," he said.

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