The battle to build one of the world’s biggest coal mines has suffered a fresh setback after Adani Enterprises Ltd. conceded it would fail to meet a March deadline to arrange A$3 billion ($2.3 billion) in financing for the project.

The December decision by the Queensland government to veto Adani’s A$900 million funding bid for a rail line meant financing would require more time to be secured, an Adani Australia spokeswoman said by phone Thursday. The Indian conglomerate said it will also consider selling a minority stake in its Carmichael project without providing further details.

The financing delay is the latest hurdle for Adani, adding pressure to its ambition to deliver the first coal production from the mine by 2020. In addition to the state government opposing a federal loan for the project, major lenders have pre-emptively excluded themselves from financing the Carmichael development because they oppose polluting fossil-fuel projects.

There have also been changes to the development of the mine and connecting rail line. Adani decided in December to build Australia’s largest coal project by itself after canceling a A$2 billion deal with contractor Downer EDI Ltd. A back-up rail option being developed by an Australian operator was also canned earlier in February. That may limit Adani’s options for hauling coal from the Galilee Basin mine to the Gautam Adani-controlled Abbot Point terminal, which faces its own refinancing deadline later this year.