Mali detained the Ivorian soldiers on July 10 after claiming they were mercenaries who had entered illegally. Ivory Coast, however, says they were part of a security and logistics contingent working under a U.N. peacekeeping mission in Mali.
"Our soldiers are not mercenaries but hostages," said government spokesperson Amadou Coulibaly in a televised statement on Wednesday, demanding their immediate release.
After mediation efforts by Togo which appeared to be stalled, Ivory Coast called for an extraordinary meeting of the ECOWAS to resolve the issue.
Three women among the captured Ivorian soldiers were released two weeks ago, according to officials.
Mali's military, which took power over the course of two coups in 2020 and 2021, could not be reached for comment.
Mali's interim President Assimi Goita this month accused Ivory Coast of providing asylum to political figures wanted by his junta and called for a "mutually beneficial" solution to the row.
Coulibaly on Wednesday called Goita's comments on a solution "unacceptable blackmail."
Mali has for a decade relied on regional allies and peacekeepers to contain an Islamist insurgency that has killed thousands of people and taken over large areas of the center and north.
But it has quarreled with neighbors and allies since taking power.
Former colonial power France pulled troops out last month, ending a 10-year mission, after a protracted row about air space, troop movements and Mali's decision to ally with Russian mercenaries from the Kremlin-linked Wagner Group, hundreds of which are now working alongside Mali's army.
ECOWAS imposed strict sanctions on Mali this year, weakening its fragile economy. It lifted them in July after rulers agreed to a 24-month transition to civilian rule.