The Greens have fired their first major salvo in their bid for City Hall, with a $6 million plan for segregated CBD bike lanes.

Greens lord mayoral candidate Ben Pennings said the party's "Safer CBD Roads" policy would create a grid of separated bike lanes throughout the inner-city.

Greens lord mayoral candidate Ben Pennings says he'd spend $6.5 million over two years to desex 40,000 cats. Credit:Michelle Smith

"Cyclists and motorists prefer to be separated to avoid fear, conflict and collisions," he said.