Greens Leader Richard Di Natale has condemned the prime minister for capitulating to “homophobic” and “bigoted” members in his party over a same-sex anti-bullying program.

Senator Di Natale said Prime Minister Malcolm Turnbull had “squibbed” his opportunity to show leadership, instead caving into conservative dinosaurs in his party.

He was responding to sweeping changes made to the program on Friday after a review found a number of lessons and resources were inappropriate for children.

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Senator Di Natale said there was still an opportunity for the prime minister to take a stance by disendorsing conservative George Christensen, who spearheaded the backbench revolt, and whose comments on the topic were “outrageous”.

“This is not some nuanced debate about the sort of program that is being delivered in a school, this is a view based in prejudice, based in homophobia, based in bigotry and it needs to be called out,” he told Sky News.

Turnbull has been criticised for a lack of leadership. AAP

Government senator Arthur Sinodinos defended the changes to the program, praising the education minister as having “walked a fine line” between supporting an anti-bullying program and removing some of the concerns that led to it becoming a “political plaything”.

He attributed the sudden heated criticisms of Safe Schools to former prime minister Tony Abbott, who introduced the program and who did not face the same level of backbench pressure, now having more time to consider policy.

“Now that Tony Abbott’s a backbencher he’s clearly had more time to focus on the nature of government programs,” he told ABC television.

Senator Sinodinos added that once Mr Turnbull has won an election, he will have more of a mandate to stamp his authority on policy.

Meanwhile, the ACT government is considering funding the program from it is own budget, after Victoria said it would defy the federal changes and use funds from the state coffers to allow the program to continue in its current form.

Education Minister Simon Birmingham rejected the Greens’ claim of homophobes in his party but acknowledged the debate drew out extreme views on both sides.

“We’ve stood up to the extremes in this debate and chartered a sensible middle course that backs the rights of parents, that protects our children in every instance,” he told reporters.