The state Labor government agreed a goal of completing 75,000 new homes a year at a national cabinet meeting in August, a dramatic increase on the current annual rate of around 48,000.
Premier Chris Minns said his government had made changes to speed up the planning system to deliver more homes, but the target would be "very difficult to meet in the short run".
"We've been clear from the very beginning that 75,000 (new homes) from almost a standing start would be difficult to accomplish in 12 months," he told the Daily Telegraph.
Opposition Leader Mark Speakman said the government was not interested in working constructively with councils or communities to produce housing solutions that met local needs.
Under Mr Minns' leadership, the NSW government has taken a range of strategies to help increase housing supply, including rezoning areas around transport hubs to allow higher-density developments.
The NSW government says planning reforms will reduce approval wait times and fast-track projects. (Dan Himbrechts/AAP PHOTOS)
The government says its reforms to the planning system will reduce approval wait times and help fast-track projects.
But Mr Speakman accused the government of taking a "back-of-the-envelope" approach to addressing the ongoing rental and housing affordability crisis.
"Chris Minns and his government rode roughshod over local communities, proposing rezonings with no consultation and next to no detail," he said.
"It's time for Chris Minns to accept our offer and discuss our proposal to work with the federal government on implementing a better targeted and more sustainable population strategy, and engage in good faith with local communities on planning reforms."
NSW's target is the highest in the country, in line with population share, however the state remains behind Victoria for housing completions.