Member for Canberra Gai Brodtmann is about to call for wide-ranging formal scrutiny of the management of the ACT's Diplomatic Estate and she is likely to get agreement for the inquiry to be launched.

The Joint Standing Committee on the National Capital and External Territories meets in Parliament House on Wednesday and will publicly question the National Capital Authority about its development plans for Stirling Park.

Ms Brodtmann said she would not comment until after the midday hearing, but The Canberra Times understands she is seeking a private meeting of the committee directly before the public session.

Ms Brodtmann will officially call for the inquiry and if she gets the nod from other committee members, terms of reference could be discussed during the public session.

Government sources said cabinet ministers Simon Crean and Bob Carr had this week been reviewing the possibility of an inquiry and looked set to tick off on the terms of reference before the National Capital Committee meets.

The inquiry will examine numerous issues concerning the establishment and continued management of diplomatic enclaves throughout Canberra.

The possibility of strata title arrangements, the use of smaller blocks and the approval of subdivisions of land already owned by foreign embassies will be raised.

A major focus of the inquiry will be the roles of the NCA, the Department of Foreign Affairs and Trade, other federal government agencies as well as the ACT government in the management of the Diplomatic Estate.

The National Capital Committee's biannual public hearing will attract more than usual attention.

A group of Yarralumla residents is outraged that Stirling Park is being considered as a site for new embassies.

A vigorous campaign against the plans is under way, with residents insisting Stirling Park and its popular Stirling Ridge should be left as open space for all Canberrans to enjoy, even though it is owned by the NCA.

Spokesman Peter McGhie said a public consultation being conducted by the NCA had given little comfort as it appeared that authority was determined to go ahead with development plans for Stirling Park.

''But we're not going away. There is still plenty we can do, even though we're up against it,'' he said.

''We will talk to government ministers and our approach now is to try and pick up on the legal angles of what the NCA wants to do.'' A parliamentary inquiry could be one way forward.

Ms Brodtmann, who is also a Yarralumla resident, has long been on the record in opposition to the development.

''Before we consider breaking ground on a new diplomatic estate, we need to have a conversation about what other opportunities already exist in Canberra,'' she told The Canberra Times in August.

''We need to exhaust the existing options in O'Malley and West Deakin, fill in earmarked sites in Yarralumla and examine possible subdivision of current sites.'' NCA chief executive Gary Rake has previously told the National Capital Committee hearings that foreign embassies have not been interested in developing sites in O'Malley and that others are reluctant to downsize holdings they have in Yarralumla.

The NCA held a public information session at the Yarralumla Uniting Church hall two weeks ago, attracting a crowd of about 80.

There is a December 14 deadline for all submissions to the NCA about the development plans.

Ms Brodtmann's inquiry would be conducted by the joint standing committee and hearings would not start until next year. Committee chairwoman, Labor MP Louise Pratt, said she had noticed that the development proposals had ''excited considerable interest'' in Canberra. ''The committee is keen to see that a good balance is struck between the needs of Canberra as a national capital and the needs of residents as a place to live,'' she said.