BERLIN/FRANKFURT (Reuters) - British Airways owner IAG (>> International Consolidated Airlines Group) has joined the field of bidders for parts or all of insolvent German airline Air Berlin (>> Air Berlin Plc), two people familiar with the matter told Reuters on Monday.

Lufthansa (>> Deutsche Lufthansa) and several other parties had put in bids for parts of Air Berlin by the deadline of Friday set by the insolvency administrator.

Air Berlin is Germany's second-biggest airline after Lufthansa. It employs more than 8,000 people.

Most potential investors appear interested primarily in the airline's roughly 140 aircraft and its airport landing and take-off slots rather than in taking over the business.

It could not immediately be learnt what parts of Air Berlin IAG has bid for.

IAG declined to comment, while officials at Air Berlin were not immediately available to comment.

Among the bidders confirmed so far, EasyJet (>> EasyJet) has said it is targeting parts of Air Berlin's short haul business.

Former Formula One driver Niki Lauda has put in a joint bid with German airline Condor, owned by holiday firm Thomas Cook (>> Thomas Cook Group).

German family-owned logistics firm Zeitfracht has offered to buy Air Berlin's cargo marketing platform, its maintenance business and regional unit LGW.

Aviation industry investor Hans Rudolf Woehrl, for his part, has offered to buy Air Berlin in its entirety, while China's LinkGlobal Logistics has asked to be given more time to formulate a bid.

(Additional reporting by Alistair Smout in London; Writing by Ludwig Burger; Editing by Georgina Prodhan)

By Klaus Lauer and Ilona Wissenbach