Equinor during the last decade made nine discoveries off Tanzania and said it was considering a liquefied natural gas (LNG) development, but in January of this year wrote off the entire book value of $982 million, citing poor economics.

The Norwegian company is the operator of Tanzania's Block 2, which it estimated to hold more than 20 trillion cubic feet (0.6 trillion cubic metres) of gas in place, while ExxonMobil also holds a stake.

Shell, meanwhile, operates Block 1 and Block 4, which are estimated to hold some 16 trillion cubic feet of recoverable gas, according to the company's website.

Talks on the future of all three blocks will restart at the initiative of Tanzania's authorities, with a focus on fiscal, legal and regulatory frameworks, an Equinor spokesperson said in an emailed statement.

"We are pleased with the sense of urgency and prioritising the government of Tanzania has placed on the Tanzania Gas and LNG Project," he added.

Norwegian business daily Dagens Naeringsliv was first to report that the talks would restart.

Shell was not immediately available for comment.

(Reporting by Nerijus Adomaitis in Oslo and Shadia Nasralla in London, editing by Terje Solsvik)