Ryanair has joined the airlines outlining preliminary interest in German carrier Air Berlin, which filed for insolvency proceedings earlier this month.

The Irish carrier confirm's comments its chief executive Michael O'Leary gave to Reuters yesterday saying the airline would be "happy to bid" for Air Berlin. But the airline stresses it would need greater access to Air Berlin's financial details to evaluate an offer for the beleaguered airline.

Ryanair has been rapidly growing its presence in the short-haul Germany. FlightGlobal schedules data for August shows Ryanair has lifted its Germany capacity by around two-thirds compared with two years ago.

Talks about acquisition of parts of Air Berlin are under way with Lufthansa, tour specialist TUI Group and, reportedly, at least one other airline.

German turnaround specialist Intro Group has also signalled its interest, while EasyJet is among others that have been linked with looking at the airline.

Germany's government has facilitated a €150 million ($177 million) bridging loan to continue Air Berlin's operations until a decision about the airline's estate has been reached.

Ryanair has sharply criticised the process and accused the government of a "conspiracy" to "carve up" Air Berlin for the benefit of Lufthansa.

The European Commission confirms it has received a complaint by Ryanair.

Air Berlin began insolvency proceedings earlier this month after key shareholder Etihad Airways, which owns 29% of the airline, pulled the plug on further investment in the ailing carrier.

A string of carriers, including Ryanair, have also shown tentative interest in another Etihad part-owned struggling carrier, Alitalia. Administrators in the Italian carrier have launched a sale process in pursuit of fresh investment generating a number of preliminary submissions of interest. The level of firm interest should become clear after the 15 September deadline for submitting binding offers.

Source: Cirium Dashboard