Eight Tunisian soldiers were killed by militants near the Algerian border.
The attack appeared to be one of the biggest attacks on the country's security forces in decades.
The incident occurred in the remote area of Mount Chaambi, where Tunisian troops have been trying to track down Islamist militants since December last year.
Meanwhile, Tunisia's Prime Minister Ali Larayedh announced that the Islamist-led transitional government will continue working despite mounting efforts to dissolve it.
He also proposed a date for fresh elections later this year.
Mr Larayedh said that: "The government will continue performing its duties and it will not abandon them, not because it is keen to hold power, and we will maintain our responsibilities until the final moment,"
He continued: "We will focus on holding the elections by the end of this year and our date is December 17."
