Iranian Oil Minister Javad Owji met Oman’s foreign and energy ministers in Muscat and discussed reviving a project to develop a shared gas field that’s been stalled for almost 20 years.

The state-run Islamic Republic News Agency reported on Saturday that Owji agreed to revisit a 2004 agreement to develop the gas layer of the Hengam field in the Persian Gulf. IRNA didn’t cite a source.

The project, estimated at the time to be worth some $1 billion in annual gas sales to Iran, originally involved laying a pipeline on the bed of the waterway to deliver 30 million cubic meters of Iranian gas daily to Oman, IRNA said.

Owji’s visit comes ahead of President Ebrahim Raisi’s trip to the Sultanate, which has sought to maintain its ties with Iran throughout the security crisis in the Persian Gulf that was triggered by the Trump administration’s withdrawal from the nuclear deal in 2018.

The Hengam field, on the eastern side of the gulf, is estimated to hold some 700 million barrels of crude oil and two trillion cubic feet of natural gas, according to the website of the National Iranian Oil Co., which manages Iran’s share of the field.

Iran holds the second-largest proven gas reserves in the world but its production capacity has been hobbled by decades of underfunding and sanctions. Last month Owji said the sector requires $80 billion of investment.

Raisi’s visit, scheduled to start on on Monday, comes as indirect negotiations between Tehran and Washington over how to restore that landmark accord remain stalled over the US’s designation of Iran’s Islamic Revolutionary Guard Corps as a terrorist organization.