Opposition leader Bill Shorten says if Labor comes to power, he will review the laws protecting Australian World Heritage-listed sites such as the Opera House, to see if they need strengthening against commercial use.

As the row escalates over the use of the Opera House sails to promote Saturday’s lucrative Everest horse race, Mr Shorten said the iconic building should “never again” be used as a “billboard”.

“I don’t want to see sites like the Opera House used for commercial purposes”, he told Fairfax Media.