The Australian National Audit Office has listed it as a “potential” inquiry in its 2018/19 work program but has yet to commit to a full audit.

Any audit would include “examining governance arrangements to support the effective implementation of programs covered by the partnership”, the ANAO said.

The federal funding is expected to deliver water quality improvements, crown of thorns starfish control, science for reef restoration, increased community engagement and improved monitoring of the reef.

However, Opposition Leader Bill Shorten says the money, which was not subjected to a tender process, should be returned, given concerns about a lack of proper process.

The foundation has previously revealed it did not suggest or apply for the funding, and no environment department officials were involved in a meeting to discuss the plan that led to the unsolicited grant.

“I can only hope that the prime minister makes a proper and detailed explanation of this whole process, and it’s certainly the case that when parliament resumes next week Labor will endeavour to get a full and proper explanation of this process,” Shorten said.

Foundation managing director Anna Marsden told the ABC the grant came as a “complete surprise” when first proposed by Turnbull, but insisted the organisation was well placed to use the money wisely.

The foundation had raised $90 million over 18 years for the reef, she said, and kept its administrative costs to a minimum.

The foundation’s board is made up of representatives from the business, science and philanthropic community and supported by high-profile companies that include: Qantas, Rio Tinto, BHP, Google and Orica.

– AAP