HNA Group, the Chinese aviation and shipping conglomerate, and a consortium led by Ontario Teachers' Pension Plan Board and Borealis Infrastructure, are in the lead to buy London City Airport from

its United States owners, according to sources close to the potential deal.

The central London airport, owned by Global Infrastructure Partners, could fetch more than 2 billion pounds ($2.8 billion).

The companies have been asked to submit another round of bids on Wednesday, and GIP has not chosen a winner, two of the sources said, adding Cheung Kong Infrastructure Holdings Ltd is also still interested in bidding.

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