Labor politicians have slammed premier Gladys Berejiklian's 're-announcement' of the promised in Edmondson Park primary school after more than two years of delays.
Macquarie Fields MP Anoulack Chanthivong said NSW Labor had been campaigning for the school to be fast-tracked for years.
However he said the Liberals had put the project on hold after the 2019 election so the Department of Education could review the Secretary's Environmental Assessment Requirements (SEARs) request.
Mr Chanthivong said it was further revealed that the school now won't be ready until 2023 - five years after it was first promised.
"Stop the spin and build our school," he said.
"Families in Edmondson Park desperately need a new school today - not in 2023.
"I share local families' frustration at having to wait more than two years before their children can walk through the school gates.
"The Government has made families wait for years for a new school in Edmondson Park. And they're still waiting.
"All we want is our fair share and a fair go for our kids."
Earlier this year Edmondson Park mum Jayda Torony told the Liverpool Champion that her 4-year-old son should be starting next year, however she decided to hold him back another year and hope there is progress on planned school in the area.
"They don't have any schools in our area that are close enough that we would want to send him to," she said.
"We are going to try our luck next year. It's frustrating... parents are left with a very difficult decision to make in regards to where they can send their kids to school.
"When we moved into the area in 2016, we were sold the dream. We were told there was a location for a school and they marked it for primary and high school.
"We were under the impression it was going to go ahead and we built home and moved in and there has been no progress."
Mrs Torony's closest school is Prestons Public School - one of 14 schools in the Liverpool and Holsworthy electorates that are operating over capacity.
Figures obtained by Labor using the powers of the NSW Legislative Council reveal Greenway Park Public School (147.5 per cent), Dalmeny Public School (186.5 per cent), Casula Public School (150.5 per cent), Wattle Grove Public School (139 per cent) and Hoxton Park Public School (132.8 per cent) as the five highest schools operating over capacity.
Opposition spokeswoman for education Prue Car said south-west Sydney was a 'school overcrowding hotspot'.
"The Liberals have approved development left, right and centre but delayed schools for years," she said.
"Now the delayed and re-announced primary school in Edmondson Park won't be ready until 2023.
"All the while almost 100 'ghost school' projects are still stuck in limbo with no construction underway."
A NSW Education spokesperson said the enrolment capacity was not the number of local students a school can accommodate, it was a guide for schools managing their out-of-area enrolments.
Education Minister Sarah Mitchell told the Liverpool Champion in September that 'the guide is being deliberately misinterpreted'.
"Schools in the area are not over capacity by up to 47 per cent and every student is accommodated at the school," she said.
"We are proudly delivering more schools than any other government in the history of NSW and this will continue."