The acquisition of bmi mainline will give British Airways an additional 56 average daily slots at Heathrow, of which up to 14 will be available to other carriers. Retained slots will be used to expand BA's operations at Heathrow with new destinations and more schedules.
Discussions with potential buyers for bmibaby and bmi Regional are continuing.
bmi is heavily loss making and is not a viable business as it stands today. Our proposals would secure around 1,500 jobs that would otherwise have been lost.
As we look to restructure the business and restore profitability, job losses are deeply regrettable but inevitable. We will work with the unions to explore as many options as possible and are already working with industry partners.
This deal is good news for our customers and will offer new destinations, new routes and new schedules in due course. For customers with bmi bookings to or from Heathrow this summer, it is business as usual and customers can continue to book with confidence.
Northern Ireland will benefit from linking in to the British Airways network, according to Secretary of State Owen Paterson.
British Airways' parent company International Consolidated Airlines Group (IAG) has confirmed the airline's Belfast-Heathrow route is secure following their acquisition of bmi.
He said: "Heathrow gives opportunities for global connections to and from Northern Ireland that are not available at the other London airports. Those connections are absolutely vital to our investment and trade.
"The European Commission decision today, opening the way for the sale to proceed, is good news for the Northern Ireland economy.
"Part of building up the economy here is making Northern Ireland readily accessible to the world and linking in to the whole BA network will be a huge advantage."
Low-fare Irish carrier Ryanair say the only significant EU airline merger that had been prohibited was its own merger with Irish airline Aer Lingus.
Ryanair boss Michael O'Leary has criticised the International Consolidated Airlines Group's acquisition of bmi.
He said: "Today's rubber-stamping of BA's purchase of bmi shows yet again that the European Commission has one rule for Europe's flag-carriers, but different rules for Ryanair.
"While we have no objection to BA's acquisition of bmi, it will undoubtedly lead to higher fares and higher fuel surcharges, and give BA/IAG even greater control (over 55% of slots) at the heavily congested Heathrow."
Jim McAuslan, general secretary of pilots' union Balpa says the International Consolidated Airlines Group's acquisition of bmi could put jobs at risk.
He said: "IAG has so far made it clear that they only intend to run the bmi mainline operation and that although they must take over the bmibaby and bmi regional businesses as part of the transaction, these businesses do not figure in their plans.
"Balpa will be looking to protect those jobs whether in IAG or with any other potential buyer. But even with the Heathrow-based bmi mainline there is a huge amount of work to do to integrate and create a sustainable operation, and we recognise this is not going to be a painless process."