A container for foodstuffs and beverages comprising a vessel having a mouth surrounded by a rim presenting an upper surface of plastics material, and a lid, comprising a diaphragm secured by an endless weld to the upper surface and covering the mouth. The diaphragm has a perforation consisting of at least one through hole and a peel strip sealingly but peelably secured over the perforation. The peel strip has a pull tab formed by a portion of the peel strip folded back on itself and situated outside the perforation. Further, the peel strip has a transverse cut across part of its width at the junction of the pull tab with the remainder of the peel strip on the side of the pull tab remote from the perforation.