An improved two-piece container seal suitable for sealing a container having a removable closure and for lining the closure comprises a flexible sealant sheet and a flexible liner sheet bonded thereto. The sealant sheet and liner sheet are of the same size and shape. The sealant sheet has a sealing surface and a first thermoplastic surface, and the liner sheet has an outer surface and a second thermoplastic surface. The first and second thermoplastic surfaces are in opposed, congruent contact with each other, and the first thermoplastic surface is ultrasonically welded to the second thermoplastic surface by an array of spaced, frangible ultrasonic welds, forming an adhesive-free interface therebetween. A method of manufacturing a two-piece container seal and a sealed container comprising a two-piece container seal are also described.