The JV now has an additional 55 days - until June 25 - to come to an agreement to settle public civil claims of about US$45.5 billion and US$6 billion filed after 19 people were killed as a result of the failure of the Fundão tailings dam.

A preliminary deal was first made in January 2017 that involved the establishment of a timeline for negotiations. That was amended to November 2017 and again until April 20, 2018.

"Until that time, the interim security arrangements and the current suspension of legal proceedings will remain in place," BHP officials said.

Operations at Samarco have remained suspended since the incident. BHP previously noted that, to resume operations safely and in a sustainable manner, the pair must secure a license for the Alegria Sul pit, a mining pit that will be used for tailings storage, and a LOC corrective operational license to relicence the entire Germano complex.

BHP and Vale each hold a 50% interest in the Samarco iron ore project.