Dar es Salaam - US Secretary of State Hillary Clinton will urge the African Union to get tougher on Libya on Monday, hoping to push Africa's leaders into a firmer stance on the ousting of Libya's Muammar Gaddafi.
Clinton, the first US secretary of state to address the 53-member AU in Addis Ababa, is also expected to warn that Middle East protests could echo in Africa, where many entrenched leaders have yet to deliver on political and economic reforms.
Clinton's AU speech comes at the end of a three-nation Africa tour during which she sought to highlight the Obama administration's drive to boost trade ties with Africa and encourage better political and economic governance.
US officials say Clinton's AU speech will carry a number of messages, chief among them the need for more African nations to support the western-led coalition demanding the ouster of Gaddafi - for years a major diplomatic and financial backer of many African leaders.
"African countries are very deeply divided and conflicted over Libya," a US senior official told reporters traveling with Clinton.
Clinton will also address rising tensions in Sudan, where fears are growing of a return to civil war after Khartoum's forces clashed in border areas with those of South Sudan less than a month before the South is due to declare independence.
US officials say Clinton will praise the AU for taking a more assertive role in regional affairs including on Ivory Coast, where it joined a successful drive to force former president Laurent Gbagbo to step down after an election widely judged to have been won by his rival, Alassane Ouattara.
But the AU's position on Libya has been murkier and the organisation has declined to join calls for Gaddafi's ouster, instead accusing Western nations of undermining its own efforts to find a solution to the conflict.
Diplomats say the lack of a clear African voice on the Libyan conflict has complicated the Libyan crisis, where Nato has unleashed air strikes to support Libyan rebels demanding Gaddafi's exit.
US officials have praised several African nations including Senegal and Mauritania for publicly declaring that Gaddafi must go.
And they say the time has come for more African countries to join the chorus - although they concede that Gaddafi's shadow still looms over the AU, which without his financial support may find it hard to pay its bills.
"We know that there is hesitation on the part of a number of African states, in large measure because of the enormous influence that Gaddafi has wielded across Africa for such a long time, and they have shown some reluctance," the official said.
Clinton is scheduled to hold meetings in Addis Ababa on Tuesday on Sudan, where diplomats said President Omar Hassan al-Bashir agreed on Sunday to pull troops out of the disputed border region of Abyei before the south secedes - a move which could help reduce tensions.
But the two sides have yet to agree on sensitive issues such as where to draw the common border and how to share oil revenues, leaving the potential for further conflict as the South prepares for formal independence on July 9.
"The United States strongly believes that a strong peacekeeping presence should be a central part of the security arrangements in Abyei," Clinton said in a joint press conference with Tanzania's President Jakaya Kikwete.
"The government of Sudan should urgently facilitate a viable security arrangement, starting with the withdrawal of Sudanese armed forces."