May 26 (Reuters) - Australia's Ramsay Health Care has offered to buy LSE-listed Spire Healthcare Group for 1 billion pounds ($1.42 billion).

The offer is for 240 pence per Spire share, a premium of 24.4% to its last close. ($1 = 0.7064 pounds) (Reporting by Arundhati Dutta in Bengaluru; Editing by Jacqueline Wong)