Extra police are being called in to quash concerns pro-Palestine protesters will cause havoc in a busy city precinct and prevent emergency workers from doing their job.
Free Palestine protesters are expected to march through Melbourne's CBD on Sunday, aiming to block the King Street Bridge.
Victoria Police Superintendent Troy Papworth said officers had tried to engage with organisers in an effort to alter the planned action, but those attempts were unsuccessful.
He warned the protest posed a "great risk" and would ultimately obstruct emergency services from performing their duties.
"Purposely blocking a major thoroughfare through the city is a risk that we just can't take and we won't stand for it," Supt Papworth told reporters on Friday.
"We've tried to engage with this group and strongly encourage them to change their plans and not occupy the bridge."
Supt Papworth warned people against causing major disruption, referencing scenes witnessed during the Land Forces action in September 2024, when protesters clashed with police and dozens were arrested.
"We do have intelligence holdings on a small group of people who intend on causing confrontation and engaging behaviour at this protest," he added.
"If people engage in criminal behaviour, they can expect to be arrested and dealt with."
Police will take to the streets on Sunday, with some officers being asked to work on their rest days, while others will be redeployed from four other regions, including Geelong.
"There will be financial impacts to this," Supt Papworth said.
It comes as thousands of people are expected to join a separate protest on the Sydney Harbour Bridge on Sunday.
NSW Police have sought to have the rally declared unauthorised, which would give officers the power to arrest participants for obstructing traffic.
An online petition calling for the march to go ahead has attracted more than 15,000 signatures.
The Free Palestine Coalition Naarm says it will march in solidarity with communities in Sydney on Sunday.
"Bring pots and pans to highlight the manufactured starvation that is causing mass casualties in Gaza," organisers said on social media.
"These shut downs are in preparation for international mass strikes, sanctions and blockades to end Israeli impunity."
Police have urged organisers in Melbourne to reconsider their plans, noting that this weekend marks the 92nd pro-Palestine rally Victoria Police have managed since October 7, 2023.
Energy Minister Lily D'Ambrosio on Friday vowed any protest activity that blocked emergency services "won't be tolerated".
"What I say about this coming weekend, is that there will be no tolerance for any protest that obstructs or interferes with the safe passage of emergency services vehicles on the roads," she said.
