Leaders of Africa and the European Union have ended their summit in Portugal by declaring a new era in relations aimed at confronting new global challenges. But they could not avoid sparring over some older issues involving human rights and conflict on the continent.

The president of the European Union, Portugal's Prime Minister Jose Socrates, closed the summit today, saying African and European leaders have turned a new page in history. He says the leaders have adopted an agenda to confront serious challenges of security, governance, migration and climate change.

Nevertheless, long-standing disagreements re-emerged during the two-day meeting.

German Chancellor Angela Merkel, in her speech on governance and human rights, accused Zimbabwe's President Robert Mugabe of harming Africa's image by quashing political freedom and human rights in his country.

Mr. Mugabe was invited to the summit despite being banned from Europe five years ago because of rigged elections in his country. His attendance prompted a boycott by the prime minister of Britain, Gordon Brown, the former colonial power in Zimbabwe.

The head of the African Union, Ghana's President John Kufuor, responded to Ms. Merkel's remarks by noting that South African President Thabo Mbeki is mediating talks between Zimbabwe's ruling party and the opposition in an effort to bring free and fair elections next year.

"It is not for anybody to just move in there and impose a solution," he said. "We want to encourage a home-grown solution so there will be a restoration of normalcy and good governance for the people of Zimbabwe."

Several European leaders met with Sudan's President Omar al-Bashir and strongly urged him to allow the deployment of U.N. and A.U. troops to end bloodshed and suffering in its Darfur region. Sudan has accepted this hybrid force, but has rejected troops from non-African countries.

Mr. Kufuor said Africa has taken the initiative on the issue, though he acknowledged it has taken some time to assemble the hybrid force.

"I believe with good will all around the hybrid force will be put together so at least humanitarian actions can be brought to the people of Darfur," added Mr. Kufuor.

African leaders also objected to the E.U. efforts to forge temporary trade agreements with developing nations, which they say will unleash excessive competition on their emerging economies. The European Union says these are needed because existing accords are due to expire at the end of this month.

E.U. Commission President Jose Manuel Barroso noted that these are temporary agreements that are meant to maintain tariff exemptions for African exports to the European Union.

"Once we have settled this transitional phase, we [will] have the time and the spirit to address development issues and important concerns that were raised also from the African Union side," said Barroso.

He said he believes that all but a few African governments will sign the interim accords by the end of the year.

The leaders agreed to hold their next summit in a couple of years on African soil.