France sent troops into its former colony last month to drive out Islamist fighters, claiming their seizure of Mali's north last year posed a threat to international security.
Paris hopes that from March it can start withdrawing its 4,000 troops but is awaiting the effective deployment of an African force (AFISMA), plagued by logistical and financing setbacks.
Meeting in Ivory Coast's capital Yamoussoukro, presidents from West Africa's regional bloc ECOWAS backed calls from France, the United States and Mali itself for the mission to receive a UN peacekeeping mandate.
"This shouldn't distract from ongoing operations on the ground," ECOWAS commission president Kadre Desire Ouedraogo told Reuters.
"It's simply an indication that, once peace has returned, we need the support of the United Nations system both for logistical and financial support."
Some two thirds of the 8,000 troops of the African-led mission (AFISMA) have deployed to Mali.
Many still lack the capacity to carry out combat operations and remain in southern Mali, leaving French forces and around 2,000 troops from Chad to secure northern towns and hunt down Islamist fighters hiding in desert and mountain redoubts.
After struggling for months to secure funding for its deployment, international donors pledged over $455 million for Mali at a meeting in Addis Ababa last month.
With the number of troops more than doubling since deployment plans were first hashed out last year, ECOWAS projects the cost of the mission at nearly $1 billion this year.
Transformation to a peacekeeping mission would ensure funding from the United Nations Department of Peacekeeping Operations and facilitate the deployment of air assets essential for moving troops in Mali's vast northern desert.
However, a decision by the UN Security Council remains weeks, if not months, away. France's UN envoy said on Wednesday that the Security Council would ask Secretary-General Ban Ki-moon to report by end-March on the possibility of creating a peacekeeping force.
Despite the rapid French advance which has seen the Islamists' former urban strongholds rapidly retaken, security on the ground in Mali remains tenuous, amid a mounting wave of guerilla raids on towns and suicide attacks.
French and Chadian forces are currently hunting die-hard Islamists holed up in the Adrar des Ifoghas mountains. Algerian television reported on Thursday that French troops there had killed Abdelhamid Abou Zeid, a leading al Qaeda field commander.