The federal government is seeking support in the Senate to pass changes to gambling laws, which would limit betting ads to no more than three per hour between 6am and 8.30pm.
Ads would also be banned from live sports broadcasts, as well as from stadiums and player jerseys under the changes.
But the coalition, Greens and other crossbenchers in the Senate say the changes do not go far enough to reduce gambling harms, meaning they are unlikely to pass without an overhaul.
Deputy Prime Minister Richard Marles said the government was working with other parties and getting the reforms right was complex.
"It's also an area where you need to strike a balance, and we believe we've done that," he told ABC Radio on Friday.
"We're not saying that people should not be able to engage in betting, but there needs to be a balance, and it's important."
Some Labor backbenchers have pushed for changes to the gambling laws.
Canberra MP Alicia Payne called for a opt-in approach to gambling ads, saying people should be able to choose if they still see them on their screens.
"I do hope we can strengthen it, particularly, when with regards to inducements," she told the ABC.
"For anyone who has had a loved one who is trying to help themselves escape from the predatory approaches of the gambling industry knows that this needs to be addressed."
Mr Marles said the gambling laws were the strongest brought before parliament.
"This has been an issue that we've been working through over a long period of time. It is complex. There are differing views across the community. We we understand that," he said.
"We are doing more in terms of breaking the link between gambling advertising and sport, more in terms of protecting our kids from being exposed to gambling advertising on TV and radio."
Independent senator David Pocock said he was working with fellow crossbenchers to put forward amendments.
"Every non-government senator thinks that this bill is not strong enough. It's not going to protect young Australians. It's not going to stop the normalisation of gambling," he told ABC Radio.
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