4.—(1) For the purposes of these Regulations a “supplier” means a person—
(a)who sought, or who seeks, or who would have wished, to be the person to whom a public supply contract is awarded, and
(b)who is a national of and established in a relevant State.
(2) Where these Regulations apply a contracting authority shall not treat a person who is not a national of and established in a relevant State more favourably than one who is.