A Chevron-led consortium on Monday signed the lease contracts for oil and gas exploration offshore Greece as the southern European country aims to become a major gas supplier in the Mediterranean. Chevron, in partnership with Helleniq Energy, signed the lease agreements with Greece concerning the exploration of four offshore blocks south of Crete and the Peloponnese. Greece picked the consortium as the preferred bidder at the end of last year following a tender, and has now made Chevron’s entry official with the signing…