Amid uncertainty over his planned expansion into Australia, sponsored and part-funded by the Abbott government, Danish climate contrarian Bjorn Lomborg is unapologetic over secret donor funding and his own, at times, large salary as head of the Copenhagen Consensus Centre.

Defending the donations, Lomborg doubled-back on a position he took late last year when he volunteered, in a Freakonomics talk in the US, "almost all" donors to the centre wished to remain anonymous.

However, in a lengthy April interview and subsequent email exchanges with Fairfax Media's Good Weekend, Lomborg spoke of only "a small number of donors" who didn't want to "paint a target on their backs [because of] the negativity and viciousness of attacks on the [the centre] from some online bloggers and activists."

The Abbott government and the University of Western Australia met a storm of criticism when it was revealed in April the Commonwealth was kicking in $4 million over four years towards the running of an Australian arm of the centre to be based on the university's campus in Perth.

Early in May, the university buckled under pressure from its academic staff and pulled out, leaving Canberra to scramble for an alternative institution to host a venture that will rely on additional, and as yet unsourced, private donor funding of about $6 million.