Humans cannot cause climate change because what killed the dinosaurs? Florida Congressman asks. Scott Kinmartin/Flickr

A Republican Congressman from Florida has said human activity could not have caused climate change because otherwise "why did the dinosaurs go extinct?"

Jeff Miller, speaking on MSNBC, told host Richard Lui that the idea climate change is manmade is "really kind of foolish".

At the start of June, President Obama unveiled historic rules to reduce coal pollution by 30%, which climate groups welcomed as a "momentous development". His announcement follows a report that found 97% of climate scientists agree climate change is being exacerbated by manmade emissions.

However, Miller was not so convinced by the bid to reduce emissions, saying climate change has always occurred.

Jeff Miller
Republican Florida Congressman Jeff Miller. Getty Images

"The truth is, climate has been changing for a long time. They call it global warming, global cooling — now everybody wants to call it climate change. Yes, the climate is changing. But it has been doing that for centuries.

"And for us to say that it is a settled argument right now I think, again, is a foolish argument to make, because there are scientists on both sides of the issue that say that's it's not settled."

Pressed on the real question, if human activity was causing climate change, Miller added: "Then why did the dinosaurs go extinct? Were there men that were causing — were there cars running around at that point, that were causing global warming? No. The climate has changed since earth was created."

The idea that climate changed caused the K/T extinction event is not a popular theory – the most widely accepted theory suggests the dinosaurs were killed off by a massive asteroid impact that led to an impact winter, making it impossible for most life to survive.

This is not the first time Miller has suggested alternative theories for climate change, however.

In August last year, he said climate change was not caused by man, but God: "I have scientists that I rely on, the scientists that I rely on say our climate has changed.

"It wasn't just a few years ago, what was the problem that existed? It wasn't global warming, we were gonna all be an ice cube. We're not ice cubes. Our climate will continue to change because of the way God formed the earth."

He also said if he were in power, he would defund the Environmental Protection Agency.