The move will mean potential new owners for some of the city’s most important heritage landmarks – the Treasury building, currently home to Star’s casino operations and the Treasury Hotel, formerly the Land Administration Building.

The company unveiled its plans in its annual report released this week, saying it is in “due diligence for the sale and partial leaseback” of the buildings.

It expects the sale to be worth around $250 million and is targeting a settlement date for next year.

Star is due to move its casino operations into the new Queens Wharf development in 2023, having successfully converted its current 50 year casino licence for the Treasury building into a 99-year licence for the new integrated resort.

Star’s sale plans include four assets – the Treasury Casino building, the Treasury Hotel building, the former State Library building, and the Queens Gardens Car Park.

Star also has sale and leaseback plans for up to half of its Sydney casino complex but no current ambitions for similar deals involving its Gold Coast and Queens Wharf properties.

The Treasury Building was erected in three stages between 1886 and 1928 and was the original headquarters for the Queensland premier and cabinet.

The imposing structure, taking up a whole city block, stood as a symbol of the fledgling state’s progression into self-government before it was converted into a casino in 1995.

The Star group had plans to repurpose the building into a combined hotel and high-end retail complex once it moved its casino operations up the road to Queens Wharf.

The former State Library building was to house an Aboriginal and European heritage centre.