The panel urged the authority against approving the development Liangis Investments proposed on Section 96, Griffith on Canberra Avenue and Franklin St, arguing it failed to meet the high architectural standards required under National Capital Authority rules.

Despite the interim panel's concerns, the authority deemed the six-storey hotel was more important to the Barr government's objectives to redevelop the city than acting on the panel's concerns.

While Chief Planner Ben Ponton said the authority's approval was on the condition the ACT Conservator also approves removing the protected London Plane tree, the Conservator's hands could be tied.

Recent legislative changes that followed an appeal by the developer effectively meant the conservator needed to heed the authority's advice, and Mr Ponton had previously written to Conservator Ian Walker outlining his position the tree would prevent redevelopment.

Kingston Barton Residents' Group committee member Richard Johnston, a life fellow of the Planning Institute of Australia, said he was concerned that despite the panel being required to have its advice considered by the authority, it seemed there was no requirement to act on such advice.

"I simply find that ridiculous, the authority would say it's been considered, but if it has, it appears no weight at all has been given to the panel's advice; so in other words it's been ignored, despite the substantial concerns the panel raised about this development," he said.

Mr Johnston, one of several objectors to the application to remove the tree, also said he was only provided the panel's advice after 5pm last Friday, some 15 minutes after the official period to make final submissions about the tree removal had expired.

In a meeting in March this year, the interim panel discussed the proposal, advising both the territory authority and National Capital Authority against allowing it go ahead, arguing it failed to meet the Manuka Circle Development Control Plan.

Among the panel's concerns were that it did not meet the high quality architectural standards required by the prominent site, it was taller than height limits, the proponent had not demonstrated removing the tree was warranted and the location of a substation on Franklin Street was inappropriate.

On the current plans for the site, the new substation would essentially replace the protected tree, and the panel was concerned it would "negatively impact on the public domain"; the panel also believed the proposed waste removal services would be insufficient.

But Mr Ponton said he did not himself approve the development application, rather it was his delegate, senior planner George Cilliers, and that his "professional advice" to the Conservator was that allowing the tree removal achieved the government's broader strategic objectives.

Mr Ponton said Mr Cilliers also took into account advice, understood provided by the developer, the tree's roots were damaging infrastructure; forming the view that "the advice from the interim panel did not warrant refusal".

He also said the NCA's chief planner Andrew Smith also supported the removal of the tree and that a substation currently elsewhere on the block be relocated to where the tree currently stands.

Mr Ponton also said that pending legislative changes the interim panel was not a formal referring entity to the authority and the authority's ability to respond to its advice was "limited and indeed, arguably non-existent".

He said changes to the Planning and Development Act to formalise the panel were imminent.

A spokeswoman for the NCA said the ACT planning authority was responsible for assessing any proposal for the site, but the NCA's advice was provided to the authority and proponent before the development application was approved.