A partial road closure in the heart of Melbourne's CBD until the end of 2021 has been labelled a blow to business by the state opposition.
Eastbound lanes of Flinders Street, between Elizabeth Street and before Swanston Street, will be closed from September 2 for due to Melbourne Metro Tunnel works.
The closure is expected to stay in place until the end of 2021.
"This is needed so we can get in and do that intensive work underneath the ground to create a new pedestrian access between what will be the new Town Hall Station across to Flinders Street Station," Transport Infrastructure Minister Jacinta Allan said on Sunday.
Pedestrians won't be able to walk down that stretch of the road but will be able to use the additional crossing, once built.
Trams will run along the road during the closure period except from October 2 to 7 this year.
"We have done everything we can to minimise this disruption. However, with a project of this size and the scale of the Metro Tunnel, that will need to see some disruption above ground while the huge bulk of the work goes on beneath," Ms Allan said.
Rail Projects Victoria chief executive Evan Tattersall said the Town Hall Station was "so massive" more space was needed and this plan minimised the impact to the busier Swanston St.
Opposition spokesman for transport David Davis slammed the government for delivering a "body blow" to local traders who will face a "significant impact".
"This will clearly cause massive congestion, massive confusion and will slow those moving through the city down," he said.
"This will be a body blow to many of those small businesses and the government need to step in and make sure that those businesses are looked after."
Ms Allan said small businesses impacted by the works may be eligible for compensation on a case-by-case basis.
Australian Associated Press