Algerian Foreign Minister Mourad Medelci, centre, greets US Secretary of State Hillary Rodham Clinton, upon her arrival at Houari Boumediene Airport, in Algiers, Algeria, Monday, Oct. 29, 2012. (Saul Loeb/AP)

The United States joined France in a diplomatic lobbying campaign Monday to win key Algerian support for an emergency military intervention in northern Mali, where al-Qaeda-linked militants are waging a terror campaign that the Obama administration warns could threaten other nations.

Secretary of State Hillary Rodham Clinton could not persuade Algeria’s longtime authoritarian leader to quickly back plans for an international military intervention that he fears would backfire.

“I very much appreciate the president’s analysis, based on his long experience, as to the many complicated factors that have to be addressed to deal with the internal insecurity in Mali and the terrorist and drug-trafficking threat that is posed for the region and beyond,” Clinton said after a lengthy meeting with President Abdelaziz Bouteflika.

Clinton said the United States and Algeria agreed to keep talking, along with potential sponsors of the antiterrorism force, including the United Nations.

Clinton was seeking agreement from Bouteflika at the start of an unrelated diplomatic trip to the Balkans. French President Francois Hollande is expected to visit Algeria in December, with a goal of finalizing regional support for a military mission early next year.

A proposed international force to confront the militants is considered impossible without Algerian support. But Algeria has been reluctant to agree to the creation of such a coalition, whose troops could push extremists out of Mali and back across its own borders.

“They’re beginning to warm to the idea, to talk through how it might work,” a State Department official said before the meetings.

Algeria is the strongest country in the North African region known as the Sahel, with unmatched military and intelligence resources. Many of the Islamist militant groups in the region originated in Algeria, where secular government forces fought Islamic militias in a civil war in the 1990s.

The spreading terrorism campaign and humanitarian crisis in Mali have drawn unusual attention in Washington over the past month. Republican presidential candidate Mitt Romney mentioned the Mali conflict at the start of last week’s foreign policy debate with President Obama, and several Cabinet officials are involved in planning for an African intervention force.

Officials have linked a group called al-Qaeda in the Islamic Maghreb to the attack at the U.S. diplomatic mission in Benghazi, Libya, last month. AQIM’s leaders are based in northern Mali, where they seized territory following a military coup that shattered the government last spring.

Many Western powers fear that the Sahara desert nation could become like Afghanistan before the 2001 terrorist attacks: a base for radical Islamist fighters to train, impose hard-line Islamic law and plot terrorist attacks in the region or beyond. The Islamists in Mali have access to a flood of weapons from bordering Libya.

Defense Secretary Leon E. Panetta said last week that the Pentagon is working with allies on a plan to deal with al-Qaeda-linked militants in Mali and elsewhere in North Africa, with U.S. assistance likely to center on intelligence and logistical support.

No American troops are expected to participate in ground combat. About a dozen members of a U.S. military team are in Mali as part of the normal embassy staff and security operation.

The Obama administration is contemplating broad military, political and humanitarian intervention in Mali, using the model of the largely successful stabilization effort in Somalia. Since 2007, the United States has spent more than $550 million to help train and supply an African proxy force of about 18,000 soldiers in Somalia, which has brought a measure of order to the nation for the first time in two decades.

Senior U.S. defense and diplomatic officials were in Paris last week for planning talks about the Mali force. France, a former colonial power in the region, has been the leader in rallying U.S. and European support for what is being called a stabilization or intervention force. The combat force would be made up of Malian soldiers and a large contingent from other African nations.

Algeria has a long, porous border with Mali and a shared internal ethnic conflict with the Tuareg minority.

Algeria initially opposed the international force as unnecessary, but has since said that although mediation talks are the best solution, Algeria would not automatically reject a military intervention. The Algerian military has dealt with the same militant leaders, many of whom are Algerian, for decades.

Clinton’s visit is an acknowledgment that despite long counterterrorism cooperation with the United States, Algeria remains wary of a campaign that could stir unrest among the approximately 50,000 Tuaregs in the country.

The Economic Community of West African States has said it is willing to send about 3,300 troops to Mali to wrest control of the north back from the militants, if it gets the backing of the United Nations and Western countries.

The African Union on Wednesday pledged to write a final operational plan for the African-led force by the end of the month, and to call for arms and equipment to be provided for Mali’s army from members and international partners.

The possible timetable, composition and mission of any European Union support for Mali will be discussed Nov. 19 by E.U. foreign ministers. Under a U.N. Security Council resolution, Secretary General Ban Ki-moon has until the end of November to help Mali develop a plan.