Flights have been permitted to resume to Bremen airport in Germany, and Hamburg and Berlin-Tegel are scheduled to reopen later on 25 May.
Air Berlin said in a statement that it has been cleared to resume services to Hamburg at 12:00 local time, Berlin-Tegel at 14:00, Sylt at 14:30 and Rostock-Laage at 17:00.
The carrier plans to resume normal operations "as soon as possible".
Source: Air Transport Intelligence news