Another federal department will pull large numbers of its public servants out of the struggling Woden town centre in just three months, as the ACT government says it can do little to stem the bleeding of jobs from the precinct.

But as Chief Minister Katy Gallagher passed responsibility for the Woden's demise to her federal counterpart on Thursday, her government confirmed that its own plans to move nearly 400 of its own bureaucrats out of Woden next year remained on track.

On Wednesday, the federal Environment Department said it would abandon its floors in Canberra's tallest building, Lovett Tower, when its lease ran out in June and move its public servants to the city's parliamentary zone.

The department did not confirm how many workers it had in Woden.

The news follows the announcement that the tower's main tenant, Veterans' Affairs, will move to Civic in June 2016 to share offices with the Australian Taxation Office in a move the government says will save $84 million over 17 years. The remaining floors in the 40-year-old landmark block are leased by Prime Minister and Cabinet in a deal that expires the same time as that of Veterans' Affairs.

Paul Weightman, chief executive of the tower's landlord Cromwell Property Group, has not responded to requests for comment.

The ACT government will shift more than 500 of its public servants from locations around the capital, including several buildings in Woden, to the northern town centre of Gungahlin, with the move expected by the middle of next year. Deputy Chief Minister Andrew Barr said on Thursday that 394 of them would come from Woden where they were occupying the rundown Callam Offices.

The northern section of the once-thriving town centre, is already beset by tens of thousands of square metres of empty offices in derelict 1960s blocks, failed retail and hospitality business and closed federal government shopfronts.

A commercial real estate agent said he was pessimistic about new large-scale office users going to Woden, while retailers at Westfield's Woden Plaza said the exodus of public sector jobs was a factor behind the deteriorating trading conditions.

Ms Gallagher said on Thursday the economic health of the town centre was dependent on decisions made by the federal government and the Assistant Minister for Regional Development, Jamie Briggs.

''Obviously this is an issue we raised with Minister Briggs when we met him a fortnight ago … really it was around decisions that the Commonwealth takes, particularly in their accommodation strategy and how that impacts on our town centres,'' Ms Gallagher said.

''Minister Briggs, as Minister for the Territories, has responsibility for the issues of the national capital.

''We've got some very strong support from Minister Briggs about maintaining town centres and the vibrancy of town centres and the role the Commonwealth plays, so I think the best we can do there is keep the communication going, make sure accommodation decisions by the Commonwealth are made mindful of the broader impact in the city.''