Diageo’s new chief executive has unveiled plans to double Guinness production while hacking back a “significant” proportion of its 30,000-strong workforce, in a strategic overhaul worthy of his nickname, “Drastic Dave” Lewis.

Shares in Diageo bounced on Thursday, as the former Tesco boss faced down the first big test of his first half-year in the job, after being parachuted in last November to revive the flagging fortunes of the UK-based drinks company.