The remaining members of that U.S. force have been tasked to conduct "liaison support" as part of French-led counterterrorism operations in the country, The Post reported on Tuesday.
Recent reports claim U.S. special operations forces had been conducting clandestine missions inside Mali since the beginning of the French operation.
Sen. John McCain (R-Ariz.) has demanded an increased U.S. military presence in Mali and West Africa as al Qaeda and other militant groups are increasingly gaining a foothold in the region.
"We will work with the French forces, assess the French and allied forces on the ground, and see to what extent we can provide equipment, training, and technology to rid Mali of these rebels, which include al Qaeda," McCain said during a trip to the country with Sen. Sheldon Whitehouse (D-R.I.) earlier this month.
However, Tuesday's admission by the Pentagon is the first time Washington has publicly admitted that American forces were on the ground in the country.
The deployments come as Paris is preparing to wind down their four-month military campaign in Mali against members of al Qaeda in the Islamic Maghreb (AQIM), the group's West African cell.
AQIM fighters and local Tuareg rebels had taken power in the northern part of Mali until French forces drove them out of the area with the support of American intelligence and airpower.
Despite that support, then-Defense Secretary Leon Panetta guaranteed that no American boots would be on the ground in Mali as part of the French operation.
But as French commanders prepare to hand their mission over to a joint Africa-United Nations peacekeeping force, Pentagon officials have little confidence local forces will be able to keep al Qaeda out of Mali.
"I have some confidence but ... I wouldn't say that it's high confidence," AQIM will not return to Mali, Assistant Secretary of Defense for International Affairs Derek Chollet told Congress this month.
"I am hopeful, but ... I don't think we're there yet," Chollet told members on the Senate Armed Services Emerging Threats Subcommittee regarding the Malian army's ability to hold the north against AQIM and other Islamic militant cells on the continent.
Should DOD take on a larger role in Mali and elsewhere on the continent, U.S. forces in the region may not have the resources to meet that demand.
Former Africa Command Chief Gen. Carter Ham told House members in March that lack of resources is forcing U.S. commanders to make some "sharp prioritization" decisions in where to focus the command's limited assets.
Military intelligence officials in the command have focused those limited assets on hot spots on the continent, such as Somalia, Mali and Libya, according to Ham.
"That's been pretty effective ... but it has left us short in other areas across the continent," he said at the time.