Lord mayor Clover Moore will call on Monday night's council meeting to take all necessary steps to ensure the Elizabeth Street Gallery Project is retained as a long-term public art project.

The wall beneath the Goulburn Street Parking station – where six Fairfax photographers installed more than 40 street works without seeking council permission last month – could also include new opportunities for artists to display their work, she said.

"Not all public art needs to be officially sanctioned or formally commissioned," Cr Moore's lord mayoral minute said.

"These photographs demonstrate how public art can transform the ugliest public spaces."

Dean Sewell – one of the photographers who spent more than three days and $4000 of their own funds installing the gallery – applauded the proposal but said he had concerns about how street art would be managed and controlled by the city.

"You'd have to question is there knowledge of photography or street art within council," he said, offering to meet council staff to discuss it.

"Once things like this become official, they can look horrible."

The city, which has long been known for its low tolerance for graffiti and street art, is currently developing a cultural policy that will help guide its approach to unauthorised public artwork.

Cr Moore said the city had strengthened its commitment to public art over the past eight years. Projects such as the Art and About Festival had also served as opportunities to increase the city's stock of public art.

Her lord mayoral minute will also call on council to take action to retain two other public artworks.

Two bronze sculptures by Caroline Rothwell, entitled Youngsters, should be retained as permanent artwork in Barrack Street, Cr Moore said.

She will also call for Always Was Always Will Be, Reko Rennie's installation on the former T2 building at Taylor Square, to be retained for two years.

"Both these works have been strongly embraced by the community and I propose that they be retained beyond the duration of the temporary art program, with Youngsters becoming a permanent artwork and Always Was Always Will Be continuing for up to two years," she said.

"The end of this period should coincide with the timing of external works on the building."