  We study the behaviour of the flux tube thickness in the vicinity of the
deconfinement transition. We show, using effective string methods, that in this
regime the square width increases linearly and not logarithmically with the
interquark distance. The amplitude of this linear growth is an increasing
function of the temperature and diverges as the deconfinement transition is
approached from below. These predictions are in good agreement with a set of
simulations performed in the 3d gauge Ising model.
