Protesters could face thousands of dollars in fines for obstructing NSW railways on top of existing penalties of potential jail terms.
The state Labor government will introduce the changes ahead of a looming blockade of the Port of Newcastle - the world's biggest coal port - although the laws will apply across NSW.
A maximum $22,000 fine will apply for blocking a railway or tramway.
The offence currently carries the threat of up to two years in jail, but the legislation does not specify a fine - unlike similar offences for obstructing roads, bridges and major facilities such as ports.
Premier Chris Minns hinted at further changes to anti-protest laws earlier in November, as the NSW Supreme Court considered a police application to stop the planned Newcastle climate protest, which it deemed an unlawful assembly.
Mr Minns said on Tuesday the fine would send a message that blocking railway lines was not acceptable.
"Protests on railway lines are seriously dangerous and disruptive, and they are not tolerated in NSW," he said.
Attorney-General Michael Daley said the proposed penalty added to strong laws already in place.
"We're balancing the right to protest with keeping the community safe and free from disruption," he said.
The NSW Minerals Council has welcomed the NSW Government's decision to strengthen penalties for those who intentionally obstruct railway lines in NSW.
"This is a sensible decision that will help deter illegal activities that put people in danger," NSW Minerals Council CEO Stephen Galilee said.
"The right to protest is important in our democracy, but it should be done safely and legally, with minimum inconvenience to others."
The state's response to protests has drawn criticism, including from within Mr Minns' own party and the union movement.
The latest change is due before parliament within days and will align with other obstruction legislation that sailed through with the support of both major parties in 2022.
The Supreme Court declared part of the changes invalid in December 2023.
Authorised protests are protected from prosecution for the offences, but police can apply to the court to deny a permit to rally organisers.
Greens MP Kobi Shetty has a bill before parliament to repeal the offences.
Australian Associated Press
