Who said "The time to act is not in 2050, it is now."?

This quote is attributed to Greta Thunberg.

The time to act is not in 2050, it is now. - Greta Thunberg

"The time to act is not in 2050, it is now."

Greta Thunberg

Climate Activist, Student Swedish Born 2003 (age 23)

"Our house is on fire. I want you to panic."

"You are not mature enough to tell it like it is. Even that burden you leave to us children."

"No one is too small to make a difference."

"A lot of people want to just continue not doing anything."