Peace talks aimed at ending 19 years of civil war in Sudan officially opened in Kenya Wednesday. The two parties signed a temporary cease-fire agreement on Tuesday and have been informally negotiating since then.

A senior official at the Sudanese embassy in Nairobi, Mohamed Dirdeiry, says the government of Sudan and rebels of the Sudan People's Liberation Army started negotiating Tuesday, as soon as they had signed the temporary cease-fire accord.

"The first issue on the agenda was power sharing," said Mr. Dirdeiry. "And they have started discussing that since, in fact, yesterday afternoon. Today we will be having a session to discuss that issue."

The cease-fire is to go into effect on Thursday.

This is the first time in Sudan's 19-year civil war that the government and rebels have agreed to a nationwide cease-fire, raising hopes that a solution can be found to end Africa's longest running war. The cease-fire is designed specifically to improve the atmosphere at the talks, and it is to be in effect as long as the talks continue. The peace talks, which are taking place in the Kenyan town of Machakos, are expected to last five weeks.

The last round of talks ended in early September when government negotiators walked out after rebel troops captured the key southern town of Torit. The government recaptured the town two weeks later, and declared it was ready to return to the negotiating table.

The United Nations and other relief agencies have welcomed the promised cessation of hostilities. The agreement requires the parties to allow unimpeded humanitarian access to all areas of Sudan. United Nations officials describe this as a very positive development that could save many civilian lives.

Some two million people have died since war broke out in Sudan in 1983, mainly from war-related famine.

Aid agencies say hundreds of thousands of Sudanese are suffering because of government restrictions on humanitarian activities in the south. This month, the Sudanese government has denied access to 61 locations.