Woodside Petroleum reported a halving in its underlying profit, and said deep uncertainy over oil prices was weighing on the prospects for its key growth project, a liquefied natural gas (LNG) development off Western Australia.

Australia’s biggest oil and gas producer said it was still unclear whether the oil price rout over the past year marked a short-term low or a fundamental shift in the market.

The Browse floating LNG partners had planned to decide on whether to go ahead with the project, last estimated by the Australian government to cost A$30 billion ($21 billion), in the second half of 2016, but Woodside would not be drawn on when a decision would be made.

"This is not the time to be reckless at all with respect to capital deployment. And this is not the time to make bets the future is going to be rosier just simply because we hope it will be," Chief Executive Peter Coleman told reporters.

In further blows to Browse, Coleman said the company had not lined up any customers for the LNG and while the project team had succeeded in slashing costs, much of those savings had been offset by the lower oil price outlook.