ACT Liberal senator Zed Seselja will announce on Wednesday he has won a commitment from the Coalition to transfer a federal government agency to Canberra's newest town centre.

The as-yet un-named agency will come from the parliamentary zone and is expected to be relatively small but the decision is significant as it establishes a precedent.

The announcement could create extra jobs, if a new building has to be erected to house the agency.

The move may suit public servants who live on the northside and wish to save on parking costs in the parliamentary zone.

Numerous government agencies are based in Parkes and Barton where workers have complained about the lack of shops and other amenities, compared to their colleagues based at town centres.

Senator Seselja also recently won federal support to keep Border Protection in Belconnen and the huge Department of Human Services in Tuggeranong.

He said it was not known at this stage which agency would be selected to be transferred to Gungahlin.

"It's unclear at this stage, it'll be a small to medium agency – small to medium agencies are in the 200 to 500 staff range roughly," he said.

"Obviously this is about value for money for the Commonwealth but it's also about giving job opportunities where people live.

"I certainly acknowledge the importance of town centres, that's why there's this commitment to Gungahlin but likewise we've got a commitment to keeping jobs in Tuggeranong, Belconnen and Woden as well.

"The Commonwealth will be looking to get best value for money – my anticipation is there's a reasonable likelihood that it would be a new building just because there isn't a lot of office space in Gungahlin town centre at the moment."

The preference will be for an agency to move from the parliamentary area so as not to impact existing town centres, Senator Seselja said.

"An agency located in Gungahlin would help to grow and strengthen the existing community with greater demand for small businesses and facilities particularly during regular business hours," he said.

"We know that the success of our local town centres is significantly impacted by the locations of government department offices, it's how Canberra was designed.

"With over 22,000 households now in the [Gungahlin] area, it's important that we see these sorts of firm commitments from our government representatives."

Senator Seselja said he had been lobbying ministers for some time about the situation in Gungahlin.

"I've had a strong focus on these local town centres, in some cases that means keeping them in an existing town centre, like DSS in Tuggeranong and Immigration in Belconnen," he said.

"Gungahlin, our newest town centre, doesn't have a Commonwealth presence and it should."

Senator Seselja's announcement is expected to be made with Finance Minister Mathias Cormann who attended last Sunday's launch of the Liberal Party's ACT team for the federal election.

Last year the ACT government opened a new office block in Gungahlin, Winyu House, to house more than 650 territory public servants, and it includes the first customer service centre as part of the Access Canberra program, new offices for the Shared Services division and a childcare centre.

On Monday Senator Seselja criticised Deputy Prime Minister Barnaby's Joyce's decision to move hundreds of Canberra-based public servants to Armidale.