New South Wales premier Chris Minns will take a tougher stance on poker machines to the next election after being pushed to adopt the approach by the party’s left.

A motion expected to pass the NSW Labor conference with unanimous support on Sunday afternoon will add a plan to take “decisive action” on problem gambling and the growing use of poker machines to its policy platform, amid surging profits for operators and accusations of inaction on reform.

The motion, seen by Guardian Australia, includes a commitment to a moratorium on licences for new machines, requiring clubs with profits of more than $20m on machines to pay more tax, and a commitment to “significantly reduce” the number of gaming machines in the state over 10 years. The commitment would mean 50% of machines are removed from operation.

The motion commits to introducing mandatory facial recognition in every gaming room to support a statewide exclusion register, policies the government is reportedly already working on.

Labor sources said the Minns government, although not directly involved, has been cooperating with negotiations and was aware of the growing grassroots support for the motion brought by Darcy Byrne, the Labor left mayor of Sydney’s inner west. It has been negotiated by the key right faction member and Unions NSW secretary, Mark Morey.

Byrne told Guardian Australia that “momentum for real reform of poker machine harm is becoming unstoppable”.

“The sentiment in the Labor party, like in our whole civil society, is that we must finally act on this scourge because too many people have been brought down by the pokies.”

Although Minns is not compelled to legislate the policy in the motion, the move comes as Labor is trying to project unity ahead of next March’s state election.

In an awkward moment for the state government on Sunday, the Labor left briefly hijacked the conference agenda to force a debate on motions submitted by 56 local branches to repeal protest laws.

The entire left faction had backed a motion for two laws to be scrapped, but the slot for discussion was placed second last on Sunday’s agenda by organisers, leaving it unlikely to be reached, which critics claimed was a move to silence debate.

Instead, during the section of the conference dedicated to country Labor issues, Angus McFarland, secretary of the left-aligned Australian Services Union (ASU), stood up with a motion to bring forward the discussion of social justice and legal affairs.

“It would be absurd if this conference did not allocate time to talk about it. Over 150 branches have moved motions in this chapter, many congratulating the government … but many have also called on the government to do better.”

“Some of the most recent [protest law] changes have been justified in the name of promoting social cohesion. Yet earlier this year, all of us saw confronting images of police breaking up peaceful demonstrations, including people engaged in peaceful prayer outside this very building,” McFarland said, to cheers and applause from left delegates.

The NSW roads minister, Jenny Aitchison, speaking against the motion, said it was “another attempt by people on the left of our party to silence the bush,” to cheers from right and country Labor delegates.

Gerard Hayes, secretary of the Labor right-aligned Health Services Union (HSU), said: “We do protest, every union in this room protests, we get outcomes because of our protests, and can I remind all of you, yesterday people were out there protesting.” The motion was rejected by the right-controlled conference.

A speech by the prime minister, Anthony Albanese, was marked by similar protests to those on Saturday, when two men unfurled a Palestinian flag as Minns entered the conference hall to speak. They were quickly removed by NSW police.

As the prime minister approached the stage on Sunday, two protesters draped a keffiyeh and a flag which read “Stop Arming Genocide. Free Palestine” over a nearby balcony. They were not removed and the flag remained visible throughout Albanese’s speech. Another protester walked out from the conference floor during the speech draped in a Palestinian flag.

Potentially embarrassing debate on Palestine and the Aukus agreement were not expected to take place on Sunday, with discussion of the party’s global affairs platform last on the conference’s agenda.

Albanese hit out at an “axis of grievance” forming between the Liberals, Nationals and One Nation, in a weekend in which speakers focused on the threat posed by Pauline Hanson’s party in NSW.

The prime minister, also under fire over federal inaction on gambling reform, left the conference before debate on NSW state policy.

The policy platform expected to be adopted by the state party calls for it to “continue to lobby the federal government to prohibit all gambling inducements” as per the recommendation in the late Labor MP Peta Murphy’s landmark inquiry report into online gambling harms.