Mining company Adani says it has struck an agreement with the Queensland Government over royalties for the proposed Carmichael mine, putting the $16.5 billion project back on track after days of uncertainty.

The Indian-based company said a final investment decision on the mine would be made at its next board meeting.

Details of the agreement between the parties are yet to be made public.

The future of the coal mine was cast into doubt earlier this month when Adani postponed its final investment decision as it waited for the Government to decide whether a "royalties holiday" would be granted.

The proposed discount was expected to cost the state hundreds of millions of dollars.

However last Friday, Premier Annastacia Palaszczuk said Adani would "pay every cent of royalties in full" but left open the option for deferred payments.

In a statement on Tuesday evening, Adani chairman Gautam Adani described the agreement as a "benchmark decision" for the mine.

"I thank the Premier, Annastacia Palaszczuk, and the elected members of the State for their continued support to make this happen," he said.

A Queensland Government spokesman said terms of the agreement could not be revealed because they were commercial in confidence.

"This is a good result for regional jobs and the Queensland economy and we've kept our election commitment to keep dredge spoil out of the Caley Valley Wetlands and the Great Barrier Reef Marine Park," he said.