Their decision comes as more questions are raised about the viability of the BG-Shell merger, which would consolidate the largest CSG reserves in the state.

Over the weekend it became clear that the Qatar Investment Authority has offloaded shares in Shell and BG worth nearly $2.2 billion, raising concerns about whether the merger has the support of major shareholders.

Shell's shares have fallen by a quarter since it unveiled its bid for BG earlier this year, while BG shares have fallen by almost 20%, and the oil price is well below where Shell and BG said the merger made sense.

QIA, the sovereign wealth fund of the world's largest LNG producing nation, has sold roughly equal amounts of shares in Shell and BG since late October, as the oil price has come under sustained pressure, and Australia has raised serious questions about the $99 billion mega-deal.

The Australian regulator is expected to make an announcement on whether it will approve the merger later this week.

The QIA is one of Shell's biggest investors, with a 4.88% stake, and also holds a 1.76% stake in BG, however some speculators have suggested the fund is merely seeking to recover cash from its more troubled investments in companies such as troubled German carmaker Volkswagen and mining giant Glencore, which have seen their value savaged in recent months.

The QIA is estimated to have around $350 billion in funds under management.

Charlie

But, away from the marbled halls of funds and the solid oak tables of boardrooms and into the fields of central Queensland, BG continues with its CSG investments vital to the success of QCLNG, with plans to drill up to 400 new wells in the Charlie project, being undertaken by subsidiary Queensland Gas Company.

The two-year drilling program now has all environmental approvals.

In addition to 300-400 wells, a large field compression station and associated pipelines and facilities which will feed into existing gas processing and water infrastructure at Woleebee Creek.

The works are part of the continuous development of QGC's tenements in the Surat Basin to needed sustain natural gas supply, primarily for export.

Leighton Contractors has been appointed as the main works contractor, will progress development and construction immediately. Major infrastructure will be built on QGC-owned property, so that part of the development should not cause any landholder issues.

QGC managing director Tony Nunan said the works west of Wandoan are an important investment in the future of QGC's operations and built on the success of the world-first production of LNG from coal seams in the past year.

The QCLNG plant has delivered 62 cargoes since first production in December 2014.

"This is a vote of confidence in the secure, long-term future of Queensland's natural gas industry, which will employ Queenslanders for many years to come," Nunan said.

"The Charlie development will help to sustain the benefits of our investment in local communities and the state, including up to 1600 construction jobs and business opportunities during the two-year project."

The Queensland Resources Council enthusiastically welcomed Charlie's approval this morning.

"The fact that the QGC's Charlie Project will create up to 1600 construction jobs, and provide other major business benefits for communities around Taroom, Wandoan and Chinchilla, is proof of the gas sector's ongoing vital importance to the Queensland and Australian economies," QRC said in a statement.

This major investment by the QGC consortium partners sees the Queensland gas export sector tap into the 160% growth in Asian gas demand out to 2040, the group said.

"The Queensland natural gas sector supports more than 114,000 Queensland jobs and 3600 businesses and accounts for 7% of the entire Queensland economy," QRC said.

The expansion announcement comes after the Australian senate approved a new inquiry into the CSG sector last week.

The Bender Inquiry was named for Queensland farmer George Bender, who killed himself last month, claiming he was "bullied" by oil and gas companies seeking to access his land.