Green Party policies once dismissed by Stormont rivals as "too radical or wingnut" are now appearing in other parties' manifestos, Clare Bailey has said.
She hailed as "historic" the passing of legislation tackling climate change, but expressed disappointment that a net-zero carbon emissions target by 2050 had been "diminished" after opponents backed less ambitious goals for methane.
The Green Party leader also branded a DUP attempt to block a bill promoting integrated education as an "abuse" of the Assembly's Petition of Concern veto mechanism.
Read more: Northern Ireland Assembly passes net-zero carbon emissions climate change legislation
Ms Bailey, who was one of Northern Ireland's first pupils to attend an integrated school, said it was "really sad" to see the Integrated Education Bill face "such fierce political resistance".
The South Belfast MLA also said she was looking forward to meeting the DUP's Edwin Poots at hustings events following his switch to her constituency from Lagan Valley.
Speaking to Belfast Live ahead of the Green Party conference on Saturday, Ms Bailey warned that more needs to be done to tackle the "climate emergency".
She said: "We have been told for decades about the implications, and now we're starting to see it unfold.
"And what you're hearing is policies and ideas that we would have been putting forward as the Green Party before would've been dismissed by other political parties as just too radical or wingnut - now you're starting to see them appear in other party manifestos."
Stormont this week passed climate change legislation tabled by Agriculture Minister Mr Poots committing Northern Ireland to net-zero carbon emissions by 2050.
But the bill has a separate reduction target of 46% for methane emissions, which are largely associated with the agricultural sector.
Ms Bailey withdrew an alternative climate bill after she and others secured amendments to make the DUP minister's legislation more ambitious.
The Green Party leader said it was "disappointing" that the "robust net-zero target has been diminished somewhat" after other parties backed the separate lower target for methane.
However, she said it was still a "very ambitious bill" and described it as a "building block" for the future.
The Assembly also this week passed Alliance MLA Kellie Armstrong's Integrated Education Bill by 49 votes to 38 despite unionist opposition.
The DUP had expressed strong opposition, claiming the bill would "prioritise one sector over all others". The UUP also opposed it but refused to back a DUP petition of concern, which would have required the vote to secure a majority of both nationalist and unionist MLAs to pass.
Ms Bailey recalled protests at the gates when she was among the first pupils to attend Lagan College in 1981 aged 11.
"It's really sad that to this day, trying to pass an integrated education bill, with minimal provision let’s be honest, is still met with such fierce political resistance," she said.
"And the DUP threatening to petition of concern it - of course, that's an abuse of a petition of concern - but to put that on for an integrated education bill is really pretty poor."
Ms Bailey also dismissed as "absolute nonsense" claims last year by Sinn Fein MLA John O'Dowd, a former Education Minister, that many integrated schools only promote a British identity.
The South Belfast MLA expressed her condolences following the sudden death last month of the DUP's Christopher Stalford.
She said it "will be interesting" to see Edwin Poots move to the constituency from Lagan Valley to succeed Mr Stalford and contest the Assembly election.
"I don't know that he’s got any connections to the constituency. But all’s fair in love and elections as they say, so we'll just have to see how it goes," she said.
"If Edwin Poots wants to come in to South Belfast and I see he does, I’ll look forward to meeting him on the hustings."
Ms Bailey also said there "wasn't a quid pro quo" in the 2019 Westminster election when she endorsed the SDLP's Claire Hanna for the South Belfast MP seat.
She said her move during the Brexit-focused election did not mean she would be encouraging Green voters to transfer to the SDLP in May's Assembly poll.
"Everybody's free to vote for who they want. My ask is that you put your number one for a Green Party candidate no matter what constituency you're in," she said.
Alliance leader Naomi Long last weekend said her party would "undoubtedly" take a position on Northern Ireland's constitutional question at some point in the future.
Asked whether the Green Party would take a position on any future border poll, Ms Bailey said they have a "wider vision for the future of these islands" focused on tackling the "climate crisis".
"What the Green Party want is a real, open, honest conversation about the future of all people on this island, and that has to be framed by climate security and a green new deal for all people," she said.
She stressed a need to "come up with a plan" and proper preparation ahead of any future referendum.
Ms Bailey said: "Let's talk to people and let's come up with a plan for what a future security will look like for all people, and let's design that, and then put it to the people, and I'll tell you exactly how I would vote when you give me the question."
Read more: Northern Ireland Assembly passes net-zero carbon emissions climate change legislation
Read more: NI Energy Strategy to reduce fuel poverty and emissions branded "missed opportunity"
