Mulet said from Bamako that the African-led International Support Mission to Mali could develop into a U.N. peacekeeping operation this summer.
"July could see the transfer of AFISMA to a U.N. stabilization mission," he said.
The U.N. Security Council in December granted a Malian request for an African support mission to help fight militant forces that took control over the north of the country in early 2012. Mali in January called for additional assistance from former colonial power France.
Mulet said the aim of the multilateral intervention was to ensure Mali remains a sovereign and united country.
"It is not to create a buffer between the north and the south," he said. "The members of the Security Council and the member states are very clear on the need for Mali to extend its authority over all its territory."
Humanitarian and U.N. rights groups have expressed concern that Malian forces may seek revenge against certain ethnic groups seen as supportive of some of the tribal militants fighting alongside al-Qaida forces in northern Mali.