The Greens have staked their campaign to hold the federal seat of Melbourne on opposing the east-west link toll road, arguing $1 billion of federal money should instead go to building a railway line to Doncaster.

Money targeted for nationally significant road projects would be redirected to public transport under the minor party's transport plan, which will be launched on Friday.

Greens MP Adam Bandt. Credit:Luis Ascui

The Greens, who according to polling are on course to lose their only lower-house seat of Melbourne, have also matched Labor's $3 billion commitment towards the Melbourne Metro rail tunnel.