One in three oil companies worldwide could be out of business by the end of 2016, according to research released Tuesday.

Roughly 175 major oil firms are facing a serious risk of bankruptcy by December, auditing and consultancy firm Deloitte concluded in a grim report on the state of the world's petroleum sector.

These at-risk companies have a combined debt of over US$150 billion, and many are facing rapidly declining asset values that could make debt repayments harder and harder if oil prices remain low.

"These companies have kicked the can down the road as long as they can and now they're in danger of kicking the bucket," Deloitte's head of corporate restructuring William Snyder told Reuters.

The report was slightly softer on oilfield service providers, which were found to be generally saddled with less debt than producers.

"Service providers tend to be more of a people business with less capital deployed, so it's easier for them to financially flex," Snyder explained.