* Rebels have seized power in Bangui, ousting president
* S. African role under scrutiny after troops killed
South African President Jacob Zuma will attend a summit of central African heads of state in Chad on Wednesday which will consider responses to the rebel takeover in Central African Republic.
The South African leader was invited by Chadian President Idriss Deby, chair of the 10-nation Economic Community of Central African States, to join the extraordinary ECCAS summit in N'Djamena on April 3, Zuma's spokesman Mac Maharaj said.
South Africa is facing questions about its role in Central African Republic after 13 of its soldiers were killed there last weekend as they fought alongside government troops trying to prevent rebels from ousting President Francois Bozize from power.
The opposition in South Africa and regional analysts have asked why a South African military training mission in Central African Republic became directly entangled in the internal conflict there.
South African media reports have suggested the soldiers were defending South African mining interests in a country rich in diamonds, uranium and oil, but officials in Pretoria have denied this. They say the presence of the 400 South African troops was covered by a 2007 bilateral defence accord with Bozize.
Maharaj told Reuters there was nothing unusual about the South African role in Central African Republic or Zuma's participation in the extraordinary ECCAS summit in Chad.
"We want to participate and benefit from the knowledge of the colleagues in the region, and share our ideas," he said.
Zuma would be accompanied at the summit by his ministers for foreign affairs, state security and defence.
On Friday, Central African Republic's new president, rebel leader Michel Djotodia, said he would review resource deals signed by the previous government and promised to step down at elections in 2016.
Djotodia was responding to questions about resource licences awarded to Chinese and South African firms by Bozize.
He added he would seek aid from former colonial power France and the United States to retrain the ill-disciplined army, a statement which appeared to be a blow to South African aspirations to maintain a role in Central African Republic.
Maharaj said South Africa's involvement there stemmed from calls by the African Union in the mid-2000s for African states to participate actively in moves to maintain stability and contribute to capacity-building in the central African state, which has a history of coups and revolts.
He said the 2007 bilateral defence accord, whose details have not been made public, derived directly from this.
Following the rebel takeover, the African Union suspended Central African Republic's membership and imposed sanctions on the rebel leaders, including Djotodia.
ECCAS groups Angola, Burundi, Cameroon, Central African Republic, Republic of Congo, Democratic Republic of Congo, Gabon, Equatorial Guinea, Sao Tome and Principe and Chad.