Council chiefs have submitted a petition to the Court of Session to allow them to use common good land for the proposed multi-million pound revamp of Union Terrace Gardens.
It is understood that if the court accepts the petition it will then be published as a public notice with residents given 28 days to submit their views.
London Olympic park designers LDA are behind the project to transform the sunken Victorian park with new features like a new entrance plaza, lift access from Union Terrace, a “halo” lighting feature and a public amphitheatre.
The scheme won permission in principle last March but not full planning permission which will now be considered by councillors later this year.
Last night a council spokesman said the petition was a “necessary legal step”.
He added: “Aberdeen City Council lodged a petition today with the Court of Session as part of the process of using common good land for the proposed redevelopment of Union Terrace Gardens.
“The land would continue to be in public ownership.”
Historian Diane Morgan, who wrote the book Aberdeen’s Union Terrace Gardens: War and Peace in the Denburn Valley, said the area had originally been a common grazing ground for cattle.
She said: “It was only in the 19th century when parks first became popular that the Lord Provost at the time considered it for that purpose. People were shocked but it went from common grazing ground to common good.”
The gardens opened in 1878.
In 2010 oil magnate Sir Ian Wood revealed his £50million plans to transform the gardens, which were backed in a public referendum, but these were later thrown out by the incoming Labour-led council in 2012.
City centre community council chairman Dustin McDonald said: “The gardens can’t be left in limbo, there needs to be progress.”
Aberdeen South MP Ross Thomson said: “This redevelopment of Union Terrace Gardens has been a long time coming and I think most Aberdonians just want to see the council get on with it.
“I was a councillor at the time of the City Garden application and I was very disappointed that opportunity was missed. However, we now have a chance to move forward and create an attraction that we can all be very proud of.”