Speaking at the inauguration, Mr Mandela said that the project was a continuation of the co-operation South Africa and Mozambique had forged in the struggle for liberation - a reference to the support given by frontline states like Mozambique in the struggle against apartheid.

"Realising the immense sacrifices of the Mozambique people as they stood with us, it gives South Africans great satisfaction to know what our joint efforts are doing for the economy and the people of Mozambique," President Mandela said.

The road is a key element of the Maputo Corridor, a seven-billion dollar development initiative, which will eventually include a rail link, an upgrading of Maputo's harbour, factories, shops and hotels.

South Africa hopes that investment in the project will help create prosperity in Mozambique and so stem the inflow of migrants seeking jobs in South Africa.

Presisdent Chissano said the project would help drive Mozambique out of poverty.

Several foreign companies have already announced major investments in the corridor, including a massive aluminium smelter project worth $1.3bn.

However, the BBC Southern Africa correspondent says there are problems because the port in Maputo is badly run down, and there is also uncertainty about how a large integrated customs and border post between South Africa and Mozambique will work.