Adani Mining has lost one of its two big external customers with Korean giant LG confirming it would not be purchasing coal from the controversial Carmichael coal mine in the Galilee Basin.

This latest set-back to build the world's largest thermal coal mine follows revelations in Fairfax Media last month that the Commonwealth Bank was no longer financial advisor to Adani.

The Carmichael coal mine appears to be spinning its wheels. Credit:Glenn Hunt

It was reported last year that LG had signed a letter of intent with Adani to purchase four million tonnes of coal. However LG issued a statement on Wednesday saying: "The LOI concluded by and between LG International Corp and Adani Mining Pty Ltd was non-binding and is invalid as of July 21, 2015 in accordance with the expiration of the LOI".

There has been no statement from Adani, nor has Adani informed the market since the LOI lapsed. A large resources project requires backing from banks and customers as pre-requisites to financial close.