A multi-stage state and council project to restore and upgrade the park, budgeted at a total of $21.98 million, was announced in 2014.

Landscaping work was expected to be completed in time for Remembrance Day last year.

But poor weather forced the council to delay the final stages, meaning the central Brisbane park was not ready for memorial services in November, disappointing those planning to recognise the Centenary of Armistice at the square.

Parts of the park and its pedestrian tunnel were reopened to the public in December 2018, while works continued on the lower section of the park next to Adelaide Street.

A Brisbane City Council spokeswoman apologised for any inconvenience caused by the delays but said the final landscaping work would be complete this month.

The years-long project includes the removal of aged and diseased trees, replanting mature pines, and multiple upgrades to create a safer and fully restored public space.

The park first opened in the 1930s on the back of public donations and was originally a memorial for World War I. It now serves as a memorial for all conflicts that Australians have served in.

In 1920, the original plan for the commemorative park was to use the entire city block between Ann, Edward, Adelaide and Creek streets, but that was gradually downsized before the state and federal governments granted the lands for the square.