Mr Barr was quizzed at a parliamentary inquiry this month about his signature on a confidential briefing paper in November 2015 which updated him on Aquis's redevelopment of the casino.

The paper has been released, heavily redacted, under freedom of information laws. It includes a paragraph that Mr Barr has ticked twice, stressing the importance of consultation with residents of Glebe Park, "in particular concerns by residents affected by Aquis' rights to Block 24 Section 65".

This is the block bought by the government in 2015 from developers Barry Morris, Graham Potts, Richard Tindale and Joe Bisa for $3.8 million plus GST.

The purchase is one criticised by the Auditor-General Maxine Cooper last year as lacking transparency, accountability rigour, and is now being investigated by an ACT parliamentary committee.

The inquiry heard from Mr Barr and key governments players as well as Mr Morris earlier this month and more witnesses will be questioned on Friday.

Liberal Leader Alistair Coe has questioned whether the government bought the Glebe Park block in a rush in 2015 to suit the casino.

But despite signing the November 2015 briefing note which referred to Aquis's "rights" to the Glebe Park block, Mr Barr told the inquiry that he was "not aware of any rights that the casino has to that block", and "there has been no decision of government to give the casino any rights".

He suggested he might have confused the Glebe Park block bought by the government with an adjacent block that the casino already owned but which was commonly understood to be public land.

"It surprised me that that [adjacent land] was actually part of the casino lease, but it is," Mr Barr said. "So it may well have been, Mr Coe, that I have confused the blocks."

In August last year, Mr Barr was asked in Question Time whether the government had been presented with any plans or concepts by Aquis that included development on the block.

Mr Barr answered that he was "not aware of any proposals for that development or any development on that site".

But on May 21 2015, Mr Barr, his chief of staff Jamie Driscoll and senior public servants met the casino owners and managers, including chairman and Hong Kong businessman Tony Fung, and his son Aquis managing director Justin Fung.

The meeting was called so the pair, who bought the casino in December 2014, could brief the government on their plans to expand the casino, including hotels and shopping, and on their bid for poker machines, which the briefing paper says is the only thing that would make the full development commercially viable.

Mr Barr has now confirmed he attended that meeting on May 21. It spells out that Aquis was considering buying land at Glebe Park for its expansion, a part of which was also to be used for a new stormwater pond, allowing the government to relocate the pond from a roundabout on Parkes Way.

A spokesman said this week that Mr Barr had been aware of earlier options being considered by the casino, but there had never been a specific development proposal from the casino for that site and there still had not been.

The government looked at buying the Glebe Park block in 2014 but negotiations lapsed in September that year. The auditor reported that in May 2015 negotiations started again, with Colliers producing a discussion paper on prices, which went to the government in June. Negotiations were held on June 19 and the price agreed, with settlement in September.

Then City to the Lake project director Tim Xirakis told the inquiry he had been blindsided by the deal, knowing nothing of the decision to start negotiating with the Glebe Park landowners until he was sent a contract on June 25. Such was his surprise, he thought it was simply the owners "trying it on".

Mr Coe has questioned the timing, given the casino briefing was on May 21, quick negotiations followed, with a deal settled on June 19, without even a formal valuation.

But then deputy chief of the Land Development Agency Dan Stewart told the inquiry that the June deal, which he negotiated, had been sparked by a cabinet sub-committee meeting also in May which decided to make a submission to Infrastructure Australia to lower Parkes Way, which meant moving the stormwater pond on Parkes Way, which meant buying the Glebe Park land.

The casino has promised a $330 million redevelopment, with swank hotels, brand shopping and restaurants. Its June statement to the Australian stock exchange refers to a revised $307 million development proposal, including new road access. When the plan was announced in 2015 the casino said it would be built by 2018, but so far there is no firm timetable, no detailed plan released and no development application.

In late August this year, the government introduced legislation that would allow the casino to run 60 fully-automated table game terminals as well as 200 poker machines. It can start operating the machines once it finishes "a prescribed stage" of a redevelopment - but details of what that means are yet to be released.