Seven consortiums have expressed interest in bidding for the lead consultant role on a 26km addition to the metro system in the Indian city of Chennai.

The bidders have responded to a tender invitation from Chennai Metro Rail (CMRL), the operator of the third-longest metro in India.

The Asian companies that have come forward are Nippon Koei of Japan and the Korea Rail Network Authority.

European contenders are Systra and Egis Rail of France, Germany’s Deutsche Bahn Engineering and Consulting.

The other two candidates are Rites, a state-owned Indian firm and US engineer Aecom.

CMRL’s map of the three lines making up the phase two extension. Line 4 is shown in blue

The winning bidder will start work early next year. The scope of the project includes planning the route of the metro and overseeing the design and construction process.

Last week, four bidders came forward for the construction contract. These included Larsen and Toubro and Tata Projects of India, a joint venture between Shanghai Tunnel Engineering and Singapore’s Who Hup Engineering, and Turkey’s Gulemark Agir.

Line 4, as it will be known, will run east to west, from Lighthouse on the Bay of Bengal to the western district of Poonamallee. It will have 30 stations, of which 12 will be underground.

The winning bidder’s work will be financed by a $360m loan from the Asian Infrastructure Investment Bank, based in Beijing.

The work is part of the $930m phase two extension to the metro, announced in 2016, which will have a total length of 104km.