Swiss commodities trader Mercuria was already playing white knight to Aegean Marine Petroleum Network before the bunker firm filed for Chapter 11 bankruptcy reorganisation in New York this week. Now it is a central partner in Aegean’s future sale or existence.

In August, Mercuria revealed it was providing a potential $1bn credit facility for Aegean as it bought out the company’s two main credit facilities and offered a $30m financing in return for 30% of its common shares and a seat on the board.