Parents met at Aussies cafe inside the building on Wednesday in shock after the childcare provider, Anglicare announced to parents via a letter that it will not be renewing its contract for Capital Hill Early Childhood Centre past this September.

Anglicare are seeking an extension of services until the end of the year, after that the future is uncertain for the hard-won service.

In a letter to parents, Anglicare NSW South West and ACT CEO Jeremy Halcrow said the "unique" circumstances of operating in the building - including new paid parking laws in the Parliamentary circle - were driving up costs after it helped start the service six years ago.

Parent Monika Sheppard who works in the Senate Committee office said it was "disappointing that parents had no advance warning in the closure".

Ms Sheppard, who has a 10-month-old baby at the service and another child at the centre said she "was able to return to work and breastfeed at the same time" because she was on site.

With long waiting lists in many ACT childcare centres, Ms Sheppard said "it will present difficulties in placing our children elsewhere".

Emma O’Sullivan, who works as a media advisor at the House of Representatives and tweets for the @AboutTheHouse account, said she was "distressed and alarmed" by the news.

"It makes being a working mother a lot easier, and I know it’s a real privilege to have a situation like this. It means a lot to me as I work five days a week," she said.

Maintaining child-staff ratios has been creating problems for the centre, according to Mr Halcrow.

In its current contract, Anglicare must have three casual places available during sitting weeks for members of parliament, senators and their staff.

Four members of parliament are currently on the centre's books for intermittent care.

When staff are sick or away, the service have been finding it hard to get replacements since casual staff need to have passes or be accompanied under security arrangements, according to Mr Halcrow.

Anglicare has also blamed space restrictions inside the building for hampering their ability to expand to incorporate 3 to 5-year-olds, which would allow for better "economies of scale".

While her children were too old to use the centre, ACT Senator Kate Lundy said the service was vital for the "long and strange hours" parents worked in the building.

Ms Lundy said former Liberal Party Senator Margaret Reid, former Labor Senator Trish Crossin, and former Member for Canberra Annette Ellis had all been instrumental in the 20-year lobby to get the service running.

Labor's early childhood spokesperson Kate Ellis has written to the Parliamentary Presiding Officers to ask them for assurance the services continue, it is believed.

The Department of Parliamentary Services (DPS) has asked for an urgent meeting with Anglicare to discuss the matter, although it is believed the DPS were aware of the difficulties brewing at the service.

It is understood the Department of Parliamentary Services are likely to offer Anglicare an extension until the end of the year, but the conditions they set out have to be approved by the Anglicare board.

The moves comes a day after the Productivity Commission issued its draft report into childcare, which called for funding from the Abbott government's Paid Parental Leave Scheme to be redirected to childcare.

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