In the continuous casting of flat metal products with a submerged nozzle having lateral outlets, a mold is equipped on each of its long sides with a pair of linear inductors that generate a magnetic field that travels horizontally over a width of the long sides and are placed on sides of the nozzle. The inductors are mounted in pairs to slide vertically over the height of the mold, and by being moved, pass from a low stirring position, located level with the outlets of the nozzle, to a high stirring position, located level with a meniscus of the liquid metal in the mold, and vice versa. Also, on passing from one position to the other, the connections for the inductors to the phases of the power supply are modified to reverse the direction of travel of the magnetic field of only one of the two inductors of each pair.