Mugabe's presence at the summit was greeted with calls to suspend him from the African Union.
"The African Union should not accept or entertain Mr. Mugabe," said Kenyan Prime Minister Raila Odinga from Nairobi, one of the most outspoken critics of Mugabe. "He should be suspended until he allows the African Union to facilitate free and fair elections between him and his opponent."
Mugabe was sworn in for a new 5-year term on Sunday at an inauguration ceremony and said in a speech that followed that he was open to discussions between his ZANU-PF party and opposition leader Morgan Tsvangirai. "Sooner or later, as diverse political parties, we shall start serious talks," the Associated Press reported.
Tsvangirai withdrew from the runoff after election-related violence killed nearly 90 of his supporters. During the course of campaigning, Tsvangirai was repeatedly detained and his chief strategist was arrested on treason charges. Six days before the election, Tsvangirai took refuge in the Dutch Embassy in Harare, Zimbabwe's capital.
Monitors from the AU condemned the poll that kept Mugabe in power, saying it did not meet their standards. The Southern African Development Community, or SADC, which represents 14 of Zimbabwe's neighbors, and the Pan-African parliament both said the vote did not reflect the will of the people and was marred by violence.
South African president Thabo Mbeki, who has served as mediator, called for Mugabe's ZANU-PF party to enter talks with Tsvangirai, the head of opposition party Movement for Democratic Change. Tsvangirai and others have criticized Mbeki, who has not openly condemned Mugabe, for favoring the long-time Zimbabwean strong-man.
Leading up to the AU summit, Tsvangirai and the MDC urged the leaders of Africa's 53 countries not to recognize Mugabe.
"I don't think it would be right for the African Union to welcome him after all he has done," said MDC vice president Thokozani Khupe in Egypt, according to Reuters.
The AU, whose membership includes all 53 African countries, is not expected to enforce new sanctions on Zimbabwe but will push for talks between the two parties similar to those brokered in Kenya. Both parties expressed willingness to enter AU-sponsored talks.
If such talks do begin for a unity government between ZANU-PF and MDC, the biggest hurdle will be determining who will lead. Both are expected to press for power-sharing negotiations based on totals from two different polls: Tsvangirai pushing to base the outcome on the March 29 election in which he won 48 percent of the vote compared to Mugabe's 43 percent while Mugabe will cite the June 27 runoff in which he won with 85 percent.
Mugabe, who is 84, came to power as a liberation hero after Zimbabwe gained independence from Britain in 1980. In Friday's runoff election, officials claimed he won more than 85 percent, though his name was the only one on the ballot.
The drawn-out election crisis compounds problems in a country already troubled by inflation rates soaring over 165,000 percent and increasing poverty. Millions of economic refuges have fled into neighboring countries.
"We are facing an extremely grave crisis," said United Nations deputy secretary general Asha-Rose Migiro at the opening of the AU summit. "This is the single greatest challenge to regional stability in Southern Africa, not only because of its terrible humanitarian and security consequences, but because of the dangerous political precedent it sets."