The race to acquire Hapag-Lloyd, the Germany-based shipping unit owned by TUI, appears to be intensifying as two potential bidders formally declared their interest in purchasing the group.

In Germany, a consortium of bidders including the city of Hamburg submitted a 'competitive' offer on Monday (21 July), the day set as the final deadline for bids, with the aim of preventing a sale abroad.

'Our consortium aims to secure the independence of Hapag-Lloyd in the long term,' said former Hamburg finance senator and consortium member Wolfgang Peiner.

In turn, Singapore-based Neptune Orient Lines (NOL) has officially expressed an interest in acquiring the group – a deal that would create the world's third largest container shipping firm behind AP Moller-Maersk and Mediterranean Shipping Co.

'It is an expression of interest which they have submitted and it is not binding,' a source close to the group told Reuters.

Interest in the possible availability of Hapag-Lloyd was sparked earlier in the year when TUI announced that it was preparing to divest the container shipping unit. Analysts estimate Hapag-Lloyd's value at approximately €5.4bn.