While other planning works for the the Beaufort Bypass progressed last week, the short section of duplication near Mt Lang Ghiran east of Ararat has been stalled by demonstrators for more than a year.

On Monday the state government welcomed the decision and said it hoped works would restart as soon as possible citing as road safety , its key objectives with the project.

"We're pleased a decision has been reached after extensive consultation and significant design revisions - we'll look to restart work as soon as possible," Projects minister Jacinta Allan said in a statement.

"The project has been approved by the Registered Aboriginal Party, Martang Pty Ltd and by the Eastern Marr Aboriginal Corporation, it has all necessary planning, environment and cultural heritage permissions and following the Federal Government's decision, we're pleased to be able to get back to work."

"It's crucial for the safety of the local community that the Western Highway upgrade is complete, and now a decision has been made we'll look to deliver this much-needed project."

There have been more than 100 crashes and 11 fatalities on the Western Highway between Ballarat and Stawell in recent years.

Major Roads Projects have already made two concessions this year including altering plans to bypass the original potential birthing trees highlighted by the Martang group and then further concessions in feburary this year to retain another 13 trees.

Legal representative for activists against the highway duplication Jidah Clark said federal environment minister Sussan Ley made a decision not to protect the land earmarked for the works.

"We were told (on Friday) the government wouldn't protect the area or sacred trees in that area under federal legislation," Mr Clark said.

"We are trying to digest the reasons for the decision and will assess how things go from here.

"There could be potential action to look for an administrative review of reasons behind her decision with maybe another court action."

Major Roads Projects Victoria confirmed the minister's decision.

Mr Clark said he was of the understanding potential works would not begin until at after July 24.

"We will continue discussions with Major Roads about how we go ahead from here," he said.

A video was posted to the Djab Wurrung Heritage Protection Embassy Facebook page at 1.30pm on Friday.

In the video, activist Zellanach Gurnaikurnai called a "red alert" for "warriors" to flock to camps on the highway and protest the decision.

Major Road Projects Victoria development and performance director Andrew Williams said MRPV was "pleased" with the government's decision.

"We're pleased that a decision has been reached and we'll be looking to recommence work as soon as possible," Mr Williams said.

Works were suspended in August at the request of the federal Department of Environment and Energy in order to undertake an assessment of the area's Aboriginal cultural heritage.

Activists have been camped at the Buangor site since June 2018 due to Aboriginal heritage concerns.

More detail as to the reasoning behind the decision is expected from the federal government in the coming weeks.