In a company announcement to the Australian Stock Exchange on Wednesday titled "Asset Sales Update", Mariner reported that an exclusive due diligence period had begun on the Killalea property, which is expected to close shortly.

Mariner managing director Bill Ireland said the fact the company was looking to sell assets was no secret but in regards to Killalea "nothing had been sold, nothing determined, so there is nothing more to say".

However, Mr Ireland added that "half-a-dozen groups had expressed interest in acquiring the (Killalea) project".

When asked about the "exclusive due diligence period", Mr Ireland said one party was very keen.

However, South Coast Labour Council secretary Arthur Rorris questioned whether the Killalea agreement could be sold and queried how the State Park was being represented as an asset.

"There are serious questions being raised here," Mr Rorris said.

"This week we received correspondence that Mariner has no lease to sell or onsell."

The Killalea State Park Trust has a development agreement with Killalea Coastal Investments, which was initially a joint venture between Mariner Financial and Babcock & Brown.

Babcock & Brown was placed in external administration in March, with Mariner taking over the KCI venture.

Mariner's Ecopoint Management, the company that was to manage the Killalea resort, was also placed in external administration in May.

Ed Gilmore of the Killalea State Park Trust said a potential sale of the agreement was "not an issue".

"The trust is optimistic about things ... we are anxious to get things moving to get some income for the park."