We prove that (Formula presented.), where (Formula presented.) is the Ramsey parameter introduced by Burr, Erdős and Lovász in 1976, which is defined as the smallest minimum degree of a graph (Formula presented.) such that any (Formula presented.) -colouring of the edges of (Formula presented.) contains a monochromatic (Formula presented.), whereas no proper subgraph of (Formula presented.) has this property. The construction used in our proof relies on a group theoretic model of generalised quadrangles introduced by Kantor in 1980.