Sudanese President Omar al-Bashir, who is wanted by the International Criminal Court on a war-crimes warrant, won't attend an African Union (AU) summit due to get under way in Uganda on Sunday, a senior Ugandan official said on Saturday.

Congolese President Joseph Kabila has also cancelled "at the last minute," while Egyptian President Hosni Mubarak is not due to attend, Deputy Foreign Affairs Minister Henry Okello Oryem told reporters.

Heads of state and government from 43 of the AU's 53 member states have confirmed that they will attend the summit in the Ugandan capital Kampala, where the problems facing the African continent have already been discussed for several days at ministerial level.

Sudanese officials and al-Bashir's lawyers have been lobbying the AU delegates to isolate the international court and support Sudan, which is preparing to file a case challenging the arrest warrants.

One of al-Bashir's London-based attorneys, Rodney Dixon, told reporters that the case will explore if a country that hasn't recognised the international court can be brought before it and if a warrant can be issued for a sitting president.

Al-Bashir had been invited to the summit despite two warrants that have been issued by the international court in The Hague, charging him with instigating war crimes and genocide in the Sudanese province of Darfur.

He was not, however, expected to attend the summit, as Kampala had previously threatened to arrest him if he participated in the first review conference of the Rome Statute - the treaty that created the international court - that was held in Uganda last month.

The Ugandan government later retracted the statement.

Al-Bashir travelled unhindered to Chad earlier this week for an official visit to that country, even though Chad has signed the Rome Statute and was thereby bound to arrest the Sudanese president.

The court has no police force and thus relies on its member states to arrest suspects, but Chadian government officials said al-Bashir would have nothing to fear in their country.

The three-day summit's theme is maternal, infant and child health and development in Africa, but the leaders are also expected to deliberate the security situation in Somalia, where the government is being besieged by Islamic militants. - Sapa-dpa