Insurance losses for the Deepwater Horizon oil rig explosion in the Gulf of Mexico could reach almost $US6 billion ($6.15 billion) according to an industry analyst.

Fitch Ratings Insurance Director Chris Waterman told a conference in Zurich that the explosion and subsequent oil spill has been the “most significant man-made catastrophe” this year.

“Current market estimates suggest the insured loss could range from $US4 billion ($4.09 billion) to $US6 billion ($6.15 billion),” he last week told insuranceNEWS.com.au.

But Mr Waterman says the total economic loss will be much greater, reaching an estimated $US35 billion ($35.8 billion).