Mali has asked the United Nations to approve an "immediate” mandate for an international force to help it recover northern parts of the country controlled by Islamist militants and drug traffickers, French Foreign Minister Laurent Fabius said on Monday.The West African country descended into chaos in March when soldiers toppled the president, leaving a power vacuum that enabled Tuareg rebels to seize nearly two-thirds of the country. But Islamist groups, some allied with al Qaeda, then hijacked the rebellion in the north to impose strict Islamic law.Citing a letter sent by Mali’s interim leaders to U.N. Secretary General Ban Ki-moon on September 18, Fabius said Mali had requested a U.N. Security Council resolution under Chapter 7 of the U.N. Charter to mandate an international force "to help the Malian army to reconquer the occupied areas of northern Mali.”Chapter 7 allows the council to authorize actions ranging from diplomatic and economic sanctions to military intervention."For several months Mali has been confronted by an unprecedented security crisis in northern areas (and has been) occupied by armed groups including terrorists, drug traffickers and all types of criminals,” Fabius, reading from the letter, told reporters."The Malian government wants the immediate military presence of this force to support Mali’s security forces to carry out this mission.”A spokesman for Ban confirmed the letter had been received and said it was being studied.Fabius said Mali’s request would be discussed at a high-level meeting on the situation in the Sahel on Wednesday during the U.N. General Assembly and that Paris had begun talks with other Security Council members on how to proceed.