Freight Link opponents 'will stand in way'

Protesters against the $1.6 billion Perth Freight Link will stand in the way of the bulldozers if need be, Greens Senator Scott Ludlam says.

The federal-funded project is rapidly gaining momentum, with a Leighton Contractors-led consortium winning the contract to build stage one, the Roe 8 highway extension, less than a week after federal environmental approval was granted.

But opponents are vowing to not give up and "will do pretty well whatever it takes, including standing in the way", Senator Ludlam says.

"We're going to try and avoid that. But if push comes to shove, we'll be here, we'll be here in numbers and we won't be moving," he told 6PR on Friday.