CAIRO, Aug 27 (Reuters) - Two Egyptian relief flights carrying more than 80 tonnes of food and medical aid for Sudan's famine and drought-afflicted south left Cairo on Thursday, airport officials said.

They said one flight was to Khartoum, and the other to the Kenyan capital, Nairobi.

The officials said that aid agencies based in Kenya would transport the aid flown to Nairobi to war-torn southern Sudan.

A late start to this year's rains, and the 15-year-old civil war between the government and the rebel Southern People's Liberation Army (SPLA), are behind the crisis in southern Sudan, where an estimated 2.5 million people need humanitarian aid.

On Thursday, Egyptian state-owned newspapers reported that Egyptian President Hosni Mubarak had ordered the relief flights. The papers also said Mubarak's wife, Suzanne, was organising a campaign with the Red Crescent to raise funds for Sudan.

"This flight is an expression of Egypt's support for Sudan during these tough times,'' one airport official said.

The SPLA is fighting for autonomy of the mainly Christian, animist south from the Arabised, Moslem north.

The United States launched missile attacks last Thursday on a factory in Khartoum, which Sudan says produced half of its medical supplies. The U.S. said the factory made chemical weapons components, which Sudan denies.

Egypt's tense ties with Sudan worsened after Cairo hosted a meeting of the Sudanese opposition this month. Mubarak has also charged Khartoum with trying to assassinate him in 1995.

In an interview with the state-owned Al Gomhuria daily, Mubarak said Sudan's leaders told him they did not object to the opposition meeting "but, as usual, they changed their minds.''