Extinction Rebellion's meeting with Michael Gove was "less s**t than expected, but only mildly", according to one activist.
Members of the group said "the rebellion has to continue" after the "disappointing" sit-down with the Environment Secretary.
Five members of the group met with Mr Gove and ministers from other departments, including the Treasury, in Westminster to discuss demands for change.
They include declaring a national emergency on climate change, reducing greenhouse gas emissions to net zero by 2025 and establishing a Citizens Assembly for people to make decisions and suggest policies.
However, they said they were left frustrated with Mr Gove.
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Member of the youth branch Felix Ottaway O'Mahony, 14, from Lambeth, south London, said: "This meeting has been very disappointing, we've set no concrete demands, he hasn't accepted any of our demands, he's avoided our demands as a whole, he isn't going to declare a national emergency.
"However, something has to be said for the fact he has recognised there is an issue."
He added: "He is going to meet us again in a month's time, which is a step forward that we will now be regularly meeting with political members.
"However, the rebellion has to continue because our demands have not been met."
Activist Clare Farrell, who was also in the room, said: “It was less s**t than I thought it would be, but only mildly.
"I was surprised to hear a radical reflection on our economic paradigm from Michael Gove when he talked about how our model is extractive and destructive - and that we need to move to a circular model. And that similarly a debt based economy doesn’t do right by young people, that it is creating a huge debt for them and that it has to change.
She added: “Unfortunately what failed to emerge was an actual way forward. I’d like to remind him that we have a 1 percent chance of hitting 1.5 degrees - that urgency wasn’t in the room.”
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Farhana Yamin, 54, a prominent climate change lawyer who glued herself to Shell's London headquarters during a week of protests, said: "I definitely think he could have taken the initiative to say Defra will show leadership that was necessary for the nation to come together, I was expecting a little bit more."
Earlier in the day, another meeting took place, with Labour shadow chancellor John McDonnell at Portcullis House, which resulted in Extinction Rebellion being asked to address the shadow cabinet.
The meeting, which lasted more than an hour, concluded with claims some progress had been made.
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Former Green Party county councillor for Stroud Sarah Lunnon, 54, who attended the meeting, said: "They gave us a concrete commitment to actually go and talk, McDonnell will ask for Extinction Rebellion to address the shadow cabinet, the shadow environment committee and also the Treasury Committee.
"I think it's really fair to say the Labour Party are listening to Extinction Rebellion, I think they've heard the voices of all those people who got arrested on the streets."
However, the MP for Hayes and Harlington did not agree to change the date in the Labour Party manifesto, which plans to halt biodiversity loss and reduce greenhouse gas emissions to net zero by 2050, but would consider a new target of 2030.
This came after Labour leader Jeremy Corbyn announced that the party will force a House of Commons vote on whether to declare an environmental and climate emergency following mass protests in London.
