Summit communications manager Shantini Munthree said the exact dates for the two-week meeting - sometimes called the Earth Summit - were still under review because the planned closing date is September 11, 2002, the first anniversary of the attacks in which more than 4,500 people died.

South Africa expects more than 60,000 delegates, activists and journalists and up to 135 heads of state to attend the two-week conference arranged as a follow-up to the 1992 environmental summit in Rio de Janeiro.

Environment Minister Valli Moosa told a news conference the event would cost between 500 million and 550 million rand ($50.6 million to $55.7 million) to stage.

He said foreign governments had pledged 70 million rand so far and he hoped their contribution would rise to 100 million rand, with South African and international business sponsors providing at least another 150 million rand.

"A small part of the total cost will be carried by the South African taxpayer - much less than half. Parliament would be comfortable if well over 50 percent of the cost is carried by others," he said.

Mashishi declined to reveal a specific target for the private sector contribution, but said his fund-raising efforts were being hampered by economic uncertainty following the September 11 attacks.

"September 11 has impacted on corporations because of the sense of a global economic slowdown. I don't foresee the companies we are talking to walking away from funding, but we may see the amounts reduced," he said.

BOLSTER AFRICA PLAN

Mashishi said he expected final pledges by the end of January and added that plans might have to be scaled down if contributions fell far short of anticipated levels.

Mashishi said plans were being made around a September 2 to September 11 schedule with an opening ceremony in a Johannesburg sports stadium on September 1 and a possible closing ceremony in the same venue on September 12.

But Munthree told Reuters that the United Nations had still to confirm the dates.

"Because of the clash with the September 11 anniversary and the security concerns that raises, the United Nations has asked for time to consider the dates.

"They have asked us to go ahead with our plans for September 2 to September 11, but there could be a change. If there is going to be a change, I don't expect it would be by more than a week or two," Munthree added.

President Thabo Mbeki's government wants the Earth Summit to bolster the New Economic Programme for African Development (NEPAD), a programme for African-led social and economic recovery based on good governance and fiscal discipline.