A technology that removes carbon dioxide from the air has received significant backing from major fossil fuel companies.
British Columbia-based Carbon Engineering has shown that it can extract CO2 in a cost-effective way.
It has now been boosted by $68m in new investment from Chevron, Occidental and coal giant BHP.
But climate campaigners are worried that the technology will be used to extract even more oil.
The quest for technology for carbon dioxide removal (CDR) from the air received significant scientific endorsement last year with the publication of the IPCC report on keeping the rise in global temperatures to 1.5C this century. Read more