South Africa's military is in urgent need of investment to ensure it can meet its international commitments after two decades of budget cuts have left it under-equipped, the defence minister said Wednesday.

In 1998, it was assumed South Africa would only deploy a single battalion to foreign missions, but by 2006 the country had committed to four to missions across Africa, overstretching its resources.

There is "an urgent need to comprehensively capacitate and equip" the South African National Defence Force (SANDF), which is underfunded and lacks enough working equipment, said minister Nosiviwe Mapisa-Nqakula.

The force's "shortcomings must be addressed to prevent the steady decline of the SANDF and the potentially disastrous consequences that could follow," she added.

A recent report by a government-appointed panel of experts said the military is in a "critical state of decline" due to chronic underfunding and warned that it may take up to a decade to get it back into shape.

It found that the meltdown has threatened the army's defence capacity at home and its ability to take part in foreign peacekeeping operations.

The army is "finding it increasingly difficult to sustain the deployment of its soldiers in the various peace missions across the continent," said the report, released last month.

South Africa's once feared and respected defence force has been hit by budget cuts and much of its equipment is no longer fit for purpose.

Defence expenditure stands at around 1.1 percent of GDP, which Mapisa-Nqakula said is below the 2.0 percent usually spent by a developing country during peacetime.

Funding problems have been caused by the post-apartheid government prioritising spending on the South Africa's previously neglected poor, particularly in black communities, she said.

"Commitments in Africa far (also) exceeded what was anticipated in the aftermath of the advent of democracy in 1994," the defence minister added.

As one of Africa's military powerhouses, South Africa has deployed troops to peacekeeping operations in the Democratic Republic of Congo and in Sudan's Darfur.

It previously sent troops to Burundi, Lesotho and Central African Republic. Its navy has also recently begun patrolling the waters off neighbouring Mozambique to ward off pirates.

South Africa is also among 10 countries that have said they would contribute to Africa's planned rapid-deployment emergency force, which is being created to swiftly intervene in crises.

"What this means is that South Africa is almost certain to increase its committment on the continent," said the minister.

South Africa's increasing commitments justify "that defence expenditure be set slightly above two percent of GDP", argued the minister.