Delta Air Lines announced Tuesday it has signed a new agreement with Air France-KLM and Virgin Atlantic Limited to expand their trans-Atlantic joint venture.The new deal signed by representatives of all three airlines sets out the governance as well as the commercial and operational terms of the expanded trans-Atlantic partnership.As part of the agreement, Air France-KLM will acquire a 31 percent stake in Virgin Atlantic currently held by Virgin Group for around $296 million. The Virgin Group will retain a 20 percent stake and Chairmanship of Virgin Atlantic.Delta officials revealed the carrier will retain its 49 percent stake in Virgin Atlantic. MORE Airlines & Airports Delta, Air France-KLM, and Virgin Atlantic are also working together to coordinate efforts to secure regulatory approvals.The airline partnership will offer the most comprehensive route network, convenient flight schedules, competitive fares and reciprocal frequent flyer benefits, including the ability to earn and redeem miles across all carriers.Additionally, passengers flying with the airlines will benefit from the co-location of facilities at key hub airports and access to each carrier’s lounges for premium passengers.