RIYADH: Dubai International, retained its position as the world’s busiest international airport last December with 3.5 million seats, the Official Airline Guide reported on Thursday. Dubai is far ahead of the second-ranked London’s Heathrow Airport with over a million more-seating capacity, OAG showed. DXB returned to 100 percent operational capacity in the middle of December with all terminals, concourses, lounges, restaurants, and retail outlets operating after the opening of the final phase of Concourse A at Terminal 3. Dubai has also seen capacity increase by 15 percent last month. It has moved up from 7th busiest last month to the second busiest global airport this month, data showed. The busiest international airports rankings are based on scheduled capacity in December, and compared to the same month in 2019, pre-pandemic. UK-based OAG, a global travel data provider started its operations in 1929 seeking to help the air travel ecosystem thrive by capturing the power of its data.