Aware that they have failed to get a fully-fledged peacekeeping force up and running, African leaders now plan a rapid-deployment emergency force, but analysts question whether it can deliver.

The African Union's "African Standby Brigade", meant to intervene swiftly in regional crises, has made little headway since preparations for a proposed force of 32,500 troops and civilians drawn from the continent's five regions started a decade ago.

Only two of five regional sections are close to becoming operational.

A new emergency force announced this week is intended to bridge the gap pending the full coming into operation of that brigade, AU security chief Ramtane Lamamra said at the organisation's headquarters in the Ethiopian capital.

South Africa, Uganda and Ethiopia have pledged troops to the interim force. Funding and troop contributions will come from member states on a voluntary basis.

The AU was criticised for not responding fast enough to crisis in Mali, after soldiers seized power in a coup in March 2012, opening the way for Islamist rebels to take over the country's north.

However, some analysts are hopeful.

Solomon Ayele Dersso, senior researcher on conflict prevention at South Africa's Institute for Security Studies, said the emergency force could work since the troops for it will be volunteered by member states with proven military capacity, instead of trying to include soldiers from every member state, as the full Standby Brigade proposes.

"One thing that's different about the new force ... is that it will be based on the principle of military capacity," he told AFP.

He cited Nigeria, Ethiopia, Chad and Kenya as states that have proven their military capacity over the past 18 months or so.

"It's nice to say all member states are equal, but we live in an Orwellian world where some states are more equal than others... and not all are in a position to make a contribution to peace and security," he said.

The new force will have to make the best of an ungainly name: the African Capacity for Immediate Response to Crises (ACIRC).

The force will be tasked with "carrying out operations of limited duration and objectives or to contribute to the creation of conducive conditions for the deployment of AU and/or UN peace operations of wider scope," AU documents said.

-- 'Let's try to do something' --

Musambayi Katumanga, a political science professor at Nairobi University, said ACIRC will work as a limited measure to contain but not solve crises.

"As a short term reactive measure to a rapidly changing situation, in which you say, 'Let's try to do something about the situation, but not resolve it'...then you could say it makes a lot of sense - but this is where the story ends," Katumanga said.

"The fact is that most states in Africa are not viable," he told AFP, arguing that most countries "are basically in the same situation as Mali, it is just a matter of time."

Roland Marchal, an analyst with the French research institute CNRS, was also pessimistic, saying AU states would find it tough to agree on when to deploy.

"Already the European Union has difficulties with 25 members. With 53 or 54 nations it's even more difficult for the AU," he noted.

"All you have to do is think back over the different crises, and ask yourself if there would have been a majority," he added. "On Central African Republic, for example, there wouldn't have been one."

On top of questions about a common political agenda there are technical problems, he added, notably regarding the capacity of troops from different continental armies to work within a single force.

He noted that Kenya prides itself on having a professional army, even if it first saw active combat in 2011, whereas Uganda and Ethiopia have armies that used to be rebel groups.

Some observers argue that the AU has accomplished great things with its intervention force in Somalia, AMISOM, whose 17,700 men from five nations are fighting to claw back territory from Al-Qaeda linked Shebab insurgents.

But Marchal said AMISOM -- funded mainly by Western backers -- is a model "that hasn't really succeeded."

"We congratulate ourselves on taking back Mogadishu, but we haven't solved anything in Somalia," he said. "The problem with AMISOM is that there is no political strategy to go with the military strategy."

Instead, the emergency force is "a proposal built on a failure (Mali) when the reasons for that failure have not been analysed," Marchal added.