N'DJAMENA - A senior US official says there is evidence of Sudanese backing for rebels fighting to topple Chadian President Idriss Deby and said Washington opposed any attempt to oust him by force.

US Deputy Assistant Secretary of State for African Affairs Donald Yamamoto said the African Union was investigating whether Khartoum had sponsored an April 13 attack by insurgents on Chad's capital N'Djamena.

"The AU is here to specifically investigate Sudan's involvement. It is evident there was a safe haven and probably logistical support provided to rebel groups," Yamamoto said, when asked about Chad's allegations of Sudanese involvement.

"The overthrow of any government is unacceptable by any group or foreign authority," he told a news conference.

Yamamoto also said Deby had to allow the opposition room to participate fully in presidential elections planned for May 3 but stopped short of calling for a postponement.

Opposition parties are boycotting next week's elections in the vast central African state, saying they will not be transparent. They have called on Deby to cancel the polls and launch a national forum to tackle Chad's problems, including corruption, an ailing economy and security woes.

"We held direct and private discussions on this issue with the President and the Foreign Minister," Yamamoto said.

"There needs to be political openness: a space and ability for civil society and the opposition to participate fully in the democratic process," he said.

Deby, who seized power in a 1990 coup but introduced multi-party elections in 1996, has said any postponement of the elections would bring a constitutional void and risk civil war.

The president has denounced the United Forces for Democratic Change group which launched a dawn attack on N'Djamena this month as mercenaries in the pay of Sudanese President Omar Hassan al-Bashir. Sudan denies the charges.

An AU delegation arrived on Friday for a six-day mission to probe Deby's claim. Chad has severed diplomatic ties with Khartoum and closed the border.

Yamamoto also said the US government would back any decision taken by the World Bank in an ongoing dispute with Chad over oil revenues, apparently dashing N'Djamena's hopes that Washington would intercede on its behalf.

Last week, Chad delayed a threat to halt oil production by an Exxon Mobil-led consortium until the end of the month after a letter from Yamamoto requested more time for talks.

The bank suspended loans to Chad in January and froze an escrow account containing Chadian oil revenues because it said the government had broken an agreement to ensure oil profits were saved for a long-term plan to fight poverty.

Chad produces about 160,000-170,000 barrels of oil per day.

"Whatever the World Bank decides we will support. We supported their original agreement that the money should be spent on poverty reduction, for the people of Chad," Yamamoto said.

- REUTERS

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