Works have commenced on the $44.8 million project to connect Constitution Avenue to Vernon Circle.
Minister for Transport and Municipal Services, Meegan Fitzharris, said the ACT government had contributed $2.8 million towards the project.
"The intersection will also be signalised to control and balance traffic flows. These signals will be synchronised with the lights at the Northbourne Avenue and London Circuit intersection to manage the impact on the broader network,” Fitzharris said.
"Measures of this kind are integral to urban renewal, to our plan to improve public transport and better integrate our road network, and I would like to thank the community for their patience while these works continue to be completed.”
The completed project will feature a dedicated bus lane in each direction from Allara Street to Anzac Parade, as well as new LED street lighting.
Senator for Australian Capital Territory, Zed Seselja, said the extension will provide improved access for motorists.
"The upgrade of Constitution Avenue is really starting to take shape and the community can really get a sense of what the road will be like once it is complete," Senator Seselja said.
"The project is expected to be completed in mid-2016. Significant below ground work has already been completed and works on the southern carriageway were finished last month.”
The works are expected to take four weeks to complete.