British Midland, the airline, is joining the Star Alliance in a dealing linking it with 14 carriers worldwide, including United Airlines in US and Singapore Airlines.
A "code-sharing" arrangement with alliance members SAS and Lufthansa will be effective from July 1st. The means that transfers booked by customers between separate airlines will function as direct flights. Code-sharing with United Airlines will be phased in, a spokesman said.
Star is a rival alliance to One-World, whose members include Aer Lingus and British Airways.