The company had slammed what it described as an "unprecedented" court decision in July which effectively blocked construction at the project.
 
At the time it said it would appeal, believing the court had misinterpreted federal mining and forestry regulations for the project, which was opposed by four conservation groups.

However it first asked the court to reconsider the decision on grounds it overstepped its authority but US District Judge James Soto said late on Monday there was no basis to reconsider the earlier ruling which had overturned the approvals for Rosemont, Reuters reported.
Hudbay director of investor relations Candace Brule told the wire service the company was disappointed with the decision and would proceed with an appeal as it studied next steps for the project.

The company had started a $122 million early works programme at Rosemont in March, anticipating a construction decision this year.

Rosemont would produce an average annual 112,000 tonnes of copper over 19 years, according to a 2017 feasibility study.

Hudbay shares had ended the day up 1.8% to C$5.09 but remain towards the lower end of a 52-week range of $3.975-$10.42.

It is capitalised at $1.3 billion (US$0.99 billion).

The miner is due to release its third quarter results on November 11.