Climate activist Greta Thunberg has responded to Donald Trump’s mockery of her speech at the United Nations by quoting the US president in her Twitter bio.

Hours after Thunberg delivered her speech at the climate summit in New York on Monday, in which she told world leaders that “the eyes of all future generations are upon you”, Trump posted a perceived jab at the 16-year-old on Twitter.

“She seems like a very happy young girl looking forward to a bright and wonderful future,” the president wrote. “So nice to see!”

On Tuesday, Thunberg responded by changing her bio on Twitter to “A very happy young girl looking forward to a bright and wonderful future.”

Her profile had previously read: “16 year old climate activist with Asperger’s”.

Thunberg’s address to the UN made headlines around the globe as she condemned the inaction on climate change.

“This is all wrong. I shouldn’t be up here. I should be back in school on the other side of the ocean, yet you all come to us young people for hope. How dare you,” she said.

“We are in the beginning of a mass extinction and all you can talk about is money and fairy tales of eternal economic growth.

“The eyes of all future generations are upon you. And if you choose to fail us I say we will never forgive you. We will not let you get away with this. Right here, right now is where we draw the line.”

Australian prime minister Scott Morrison responded to Thunberg’s speech by saying that he doesn’t want to subject children to “needless anxiety”.

“I want children growing up in Australia to feel positive about their future, and I think it is important we give them that confidence that they will not only have a wonderful country and pristine environment to live in, that they will also have an economy to live in as well,” he told reporters.

“I don’t want our children to have anxieties about these issues.”

In July, German chancellor Angela Merkel said young activists like Thunberg have pushed her government to act faster on climate issues.

“The seriousness with which Greta, but also many, many other young people, are telling us that this is about their lives, and that their life spans extend further, has led us to approach the matter more resolutely,” she said.