Northumbrian Water announced on Friday that it had received an informal takeover approach from Hong Kong billionaire businessman Li Ka-shing\'s Cheung Kong Infrastructure Holdings. \"The board of Northumbrian Water confirms that it has now received a non-binding indicative proposal from Cheung Kong Infrastructure Holdings Limited regarding a possible cash offer for the company,\" it said in a brief statement. \"There can be no certainty that an offer will be made. A further announcement will be made when appropriate.\" Northumbrian Water supplies water to northeastern England and has about 2.6 million customers. Cheung Kong Infrastructure Holdings (CKI) had already announced on Tuesday that it was \"in the preliminary stages\" of assessing a bid for Northumbrian Water. CKI is a division of Cheung Kong Holdings, which is owned by Hong Kong\'s richest man Li Ka-shing.