A system for mounting wall panels to a wall, includes wall panels, each including a main wall panel, and at least two bent end sections with a cut-out section and a wall thickness; and a plurality of main fastening extrusions, each including a base section to be secured to the wall, and two parallel, spaced apart flexible and resilient bent end securing walls extending from the base section, each bent end securing wall including a projection facing the other bent end securing wall, the bent end securing walls spaced apart corresponding to the wall thickness of two bent end sections, such that pressing of the bent end sections into the spacing between the bent end securing walls causes biasing away of the bent end securing walls until the projections engage in respective cut-out sections with the bent end sections being at least in near abutting relation.