New oil findings at a deeper layer in Guyana's seabed could help adding billions of barrels to what is already the world's largest oil discovery in 20 years, Hess Corp. Chief Executive John Hess said on June 2 during a webcast.

Hess has a 30% stake in an Exxon Corp.-led consortium that has found 11 billion barrels of oil and gas in the tiny-South America country.

The group, which made most of its more than 30 oil discoveries at 15,000 feet depths, has started to drill at 18,000 feet, he said.

"We are starting to find other attractive deep prospects," Hess said at Bernstein's Annual Strategic Decisions conference.

"There are multi-billion barrels remaining on top of" the 11 billion barrels found so far, he said.

The Fangtooth discovery well drilled earlier this year at 18,000 feet, for example, could underpin another production unit on its own, Hess said, pending appraisal wells.

Projects in Guyana are ahead of schedule, he said. Exxon's third planned platform may now start production at Payara as soon as the third quarter 2023, from 2024 before, Hess said.

Guyana's rising production will help Hess grow output at a 10% annual rate, Hess said. It also exempts the company from having to make acquisitions to sustain higher dividends to shareholders, he said.

"We are not interested in M&A," Hess said. "We don't need to do it."