The present invention relates to an improvement of the foldable box with a resealable spout described in the main patent and is characterized by the fact that the two lateral angular sectors constituting the spout (22, 23) are extended by two upper angular sectors (32, 33) to which they are attached by two fold lines (34, 35), the two upper angular sectors (32, 33) being substantially symmetrical in shape to the lateral angular sectors (22, 23), the central (20, 21) lateral (22,23) and upper (32, 33) angular sectors forming said spout.