ADDIS ABABA, Ethiopia — Secretary of State Condoleezza Rice on Wednesday urged the leaders of some of Africa's most unstable states to restore security and shore up faltering peace deals, but she didn't seek or win assurances from their foes to do likewise.

In a hectic series of meetings in the Ethiopian capital, Rice tried to calm the volatile Great Lakes region, ease rising tensions between Ethiopia and Eritrea and violence in Somalia, cool the conflict in Sudan's Darfur province and salvage a shaky north-south Sudan peace deal.

Yet, while the officials she saw pledged to work to those goals, their opponents were either not invited or refused to attend the talks in Addis Ababa, which is home to the African Union.

With her host, Ethiopian Prime Minister Meles Zenawi, Rice warned against a feared return to war between his country and archrival neighbor Eritrea over border tensions that have risen steadily since a 2000 peace deal ended a two-year conflict in which tens of thousands died.

Rice said in a statement she had "urged the prime minister to avoid any acts that might heighten friction between Eritrea and Ethiopia and to take concrete steps to lessen tensions on the border. There must not be a resumption of hostilities initiated by either side."

There was no immediate comment from the Ethiopian side and Rice, who had a working dinner with Meles, did not meet with Eritrean officials, who have repeatedly accused the United States and others of siding with Ethiopia.

Officials from Sudan's ruling party, which is accused of backing militia responsible for atrocities in Darfur and signed a 2005 peace deal with southern rebels, were no-shows at the talks on Sudan, an apparent snub to Rice who nonetheless pressed for peace.

"The parties to this agreement are obligated to make every effort to guarantee its success," Rice said of the north-south peace pact. The south has pulled out of a unity government with the north, accusing Khartoum of violating principals parts of the accord.

"We also urge all players in Sudan to end the violence in Darfur and to support everyone in the country who wants peace, security, and prosperity for themselves and their children," Rice said. But the meeting was not attended by representative of Darfur rebel groups.

With officials from Somalia, where an Islamic insurgency accused of al-Qaida links has killed thousands of civilians this year, and its neighbors, Rice called for the quick deployment of African peacekeepers to bolster a meager Ugandan force and replace Ethiopian troops that invaded last year.

"We do believe the Ethiopian forces should not have to stay in Somalia past a certain point, and that will require peacekeeping forces, very robust peacekeeping force, and so that will be part of my discussions here," she told reporters at a news conference.

The United Nations says Somalia is facing the worst humanitarian crisis in Africa, with millions displaced from their homes due to ongoing violence, and Rice said an immediate end to fighting would be critical to assisting them.

"A cease-fire agreement with key stakeholders, such as clan and business leaders, would be an important step in helping to facilitate delivery of humanitarian assistance, and would reduce the level of violence and create the conditions for longer-term security sector reform," she said.

Peacekeepers have tried to pacify Somalia before, with tragic results. More than a decade ago, a massive U.N. relief operation was launched for thousands of civilians left starving because of fighting in Somalia. But 1993 attacks by Somali militiamen that brought down two Black Hawk helicopters and killed 18 U.S. servicemen were followed by the withdrawal of U.S. troops and the eventual end of the U.N. peacekeeping operation.

Rice met with Somalia's new prime minister but not with its ailing president, who was receiving medical treatment in Kenya or with members of the Islamist community not believed to have terrorist affiliations.

She urged the prime minister, who is coping with a Cabinet insurrection that saw five ministers resign in the past two days "to really reach out to all the elements that are not associated with terrorism."

Shortly after arriving in Ethiopia, Rice met leaders from Burundi, Rwanda, Uganda and Congo to discuss fighting in eastern Congo that threatens stability throughout their Great Lakes region.

Rice said dealing with rebels in eastern Congo is critical to re-establishing normalcy in a region that has been devastated by decades of war and genocide that have killed millions.

Associated Press Writer Anita Powell contributed to this report from Addis Ababa, Ethiopia.