The proposed disposal of up to 140 hectares of farmland joined to Hurlstone Agricultural High School was originally expected to fetch up to $240 million and was included in the November mini-budget.

In response to community concerns the State Government recently announced plans to conduct a public inquiry into whether the land should be sold.

The member for Macquarie Fields, Andrew McDonald, called for the public inquiry in February after consulting the education minister's office about his intentions.

Yesterday, he said he would actively oppose the sale at "any inquiry" to be held.

"I urge the Government to abandon this proposed sale."

Asked if the Labor Party had conducted any polling on the issue, Dr McDonald said: "I don't need formal polling to tell me how the community feels about this."

Internal documents from the Minister for Education, Verity Firth, revealed the Government had planned to fund the Hurlstone inquiry from proceeds of the land sale - despite the sale being the object of the inquiry.

Dr McDonald said he had used the Easter break to reconsider all aspects of the sale.

"I believe the loss of the land outweighs any possible benefits.

"The land is valuable due to the educational opportunities, green space and heritage benefits that it provides."

Ms Firth yesterday said she would proceed with the inquiry, which would now be funded from the Department of Education's assets management budget.