Victoria's parliament has placed animal activists in its sights, vowing to review the state's legal protections for farmers against trespassing animal rights activists.

The Andrews government is supporting the Liberal and Nationals parties' push for a state parliamentary committee to consider the effectiveness of current laws in deterring activists.

About 150 animal rights activists blocked the intersection of Flinders and Swanston streets in Melbourne, calling for an end to animal cruelty. Credit:Zach Hope

But anti-cruelty campaigners say the public would never learn about what happens on farms and in abattoirs if it weren't for the aggressive tactics of a handful of "brave whistleblowers".

The parliamentary push comes weeks after dozens of vegans shut down Melbourne's CBD and took over farms and slaughterhouses, as part of co-ordinated animal rights protests across the country.