The sell-out debate between Ken Ham and Bill Nye is to be live streamed free of charge, organisers have confirmed.

Tickets for the highly anticipated event on February 4 sold out less than two minutes after going on sale, leaving many people disappointed.

Organisers had originally announced plans to stream the debate for a small fee to help cover the costs of the event. 

But the debate will now be available live online and free at www.debatelive.org

Organisers are making the live stream available in HD suitable for large screen viewing in schools, churches and other public venues.

Bill Nye is an American science educator, comedian, television host, also affectionately known as the Science Guy.

He'll be going head to head with Answers in Genesis founder Ken Ham at the Creation Museum's 900-seater Legacy Hall in Cincinnati.

The question they will be seeking to answer is: "Is creation a viable model of origins in today's modern scientific era?"

The debate kicks of at 19:00 EST.

Secularist Dan Arel has criticised Nye for agreeing to take part in the debate.  Writing on the Richard Dawkins Foundation's website, he said: "Scientists should not debate creationists. Period.

"Creationism vs. evolution however is not worth debating. Why? Simple, there is nothing to debate. Evolution is a scientific fact, backed by mountains of evidence, peer-reviewed papers you could stack to the moon and an incredible scientific community consensus. Creationism is a debunked mythology that is based solely in faith."

Nye told CNN he agreed to take part in the debate to educate people on a "scientifically illiterate" view of the earth's origins and development.

Ham said the debate would "highlight the fact that so many young people are dismissing the Bible because of evolution, and even many young people who had grown up in the church decided to leave the church because they saw evolution as showing the Bible could not be trusted".