Richard Dawkins has again refused to debate world-renowned apologist William Lane Craig on the rationality of faith and the existence of God.

Many believe that Craig’s upcoming “Reasonable Faith” tour in the UK is intimidating Dawkins, who refuses to engage on a one-on-one talk with the leading Christian apologist, famous for his revival of the Kalam cosmological argument which asserts that God caused the universe to first exist.

But Dawkins, defending his decision, previously shared during a panel that Craig was not a worthy opponent.

“I always said when invited to do debates that I would be happy to debate a bishop, a cardinal, a pope, an archbishop, indeed I have done those, but I don’t take on creationists and I don’t take on people whose only claim to fame is that they are professional debaters; they’ve got to have something more than that. I’m busy.”

Though the author of The Blind Watchmaker and The God Delusion found Craig’s background insubstantial, many of his fellow atheists have debated with the theologian, including Bart Ehrman, Richard Taylor, and two of the “Four Horsemen” of New Atheism, Sam Harris and Christopher Hitchens.

In fact, Harris once described Craig as “the one Christian apologist who has put the fear of God into many of [his] fellow atheists”.

Not only a “professional debater” as Dawkins labelled him, Craig has authored or edited over 30 books, and is the current research professor of philosophy at the Talbot School of Theology in California.

He has made significant contributions to the philosophy of time and religion, and also works as a New Testament historian.

Dawkins’ refusal to debate Craig has become an international issue, with many critics and intellectuals interpreting the British evolutionary biologist’s actions as a sign of cowardice.

“The absence of debate with the foremost apologist for Christian theism is a glaring omission on your [cover letter] and is of course apt to be interpreted as cowardice on your part,” Daniel Came, an atheist and Worcester College philosophy lecturer wrote to Dawkins in a letter, according to The Telegraph.

“I notice that, by contrast, you are happy to discuss theological matters with television and radio presenters and other intellectual heavyweights like Pastor Ted Haggard of the National Association of Evangelicals and Pastor Keenan Roberts of the Colorado Hell House.”

Using his own commandment against him, “Never cut yourself off from dissent,” Dawkins has ignored the backlash surrounding the debate by continuing to decline requests from Craig to defend his arguments outlined in The God Delusion.

Nonetheless, the Talbot professor is still opening up the opportunity for Dawkins to accept his invitation to debate one-on-one with him at Oxford’s Sheldonian Theatre on October 26, though many are uncertain whether he will show or not.

Dawkins earlier refused public debate invitations with the British Humanist Association, the Cambridge Union, Premier Radio and the Oxford Christian Union as well.

He told The Daily Telegraph that he had “no intention of assisting Craig in his relentless drive for self-promotion.”

While some support and respect Dawkins’ choice in declining the debate, others still hope that he will accept Craig’s invitation.