Stirring up a fresh controversy, Anil Ambani's group has questioned the role of the AAI chairman and a top civil aviation ministry official in awarding bids for modernisation of Delhi and Mumbai airports, alleging that they favoured the GMR-Fraport consortium for the Delhi airport contract.

Reliance [Get Quote] Airport Developers, which has challenged the entire bidding process in the Delhi high court, wrote a protest letter to each member of the Empowered Group of Ministers on airport modernisation highlighting the conflict of interest of AAI chief K Ramalingam and civil aviation ministry joint secretary Sanjay Narayan, who had participated in the bidding procedure.

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In its letter, Reliance, which lost the Delhi airport to GMR despite being the highest financial bidder, alleged that the two officials played an active role aimed at excluding the company and favouring the rival, informed sources said.

Reliance said the two officials were also on the board of Hyderabad International Airport Ltd, which is a joint venture between GMR and Airport Authority of India but did not disclose this at any time, either in public or at the decision making body -- eGoM.

While the two officials were part of the government review committee on the bids for the two airports, the AAI chief was also member of inter-ministerial group to recommend on bids to eGoM.

Terming their role as 'unfair and improper,' the communication said the last minute changes in the tender conditions as stipulated in the Request for Proposal were also untenable.