"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'"