Alan Joyce will press charges against the man who shoved a pie in his face.

Despite receiving an unreserved apology, Alan Joyce will press charges against the man who shoved a lemon meringue pie in his face and says the incident has only made him more determined to campaign for same-sex marriage.

Perth man Tony Overheu says he smeared Mr Joyce with the pie in protest against the Qantas chief executive’s “corporate bullying” over gay marriage.

Mr Overheu, a former farmer and devout Christian, apologised via email for Tuesday’s stunt, but Mr Joyce isn’t turning the other cheek.

“My intention is to send a message that this type of behaviour isn’t acceptable and that I will have every intention of pressing charges,” he told reporters on Wednesday.

Mr Overheu, 67, left a room of more than 500 people aghast when he strolled up to Mr Joyce and shoved a $25.95 lemon meringue pie in his face during a speech at a business breakfast at Perth’s Hyatt Regency hotel.

Watch: Two young gay people answer the questions they’re sick of hearing. Post continues below.

He revealed his modus operandi on Wednesday, saying he hid in a small gap behind the podium and waited for two hours while the audience ate breakfast before ambushing Mr Joyce.

Mr Overheu claims the Qantas CEO is part of a network of corporations including Airbnb, Wesfarmers and Holden that are trying to impose gay marriage on Australians.

He was referring to 20 corporate chief executives signing a letter in March urging Prime Minister Malcolm Turnbull to legislate same-sex marriage and not hold a gay marriage plebiscite.

Mr Overheu says he attended a barbecue on the weekend, in which other people were also "pee'd off" about "special interest groups" overriding the individual and society's will.

"I feel very deeply about this theme of corporate bullying ... middle Australia completely rejects corporate bullying aimed at social engineering," he told 6PR radio.

"It would appear Alan Joyce is part of a network trying to subvert the federal parliamentary process around the issue of marriage equality.

"Figures overstepping the line have got to anticipate there will be push back."

But Mr Joyce, who is gay, said he would not be intimidated, which he believed was Mr Overheu's intention.

Mia Freedman sits down with Prime Minister Malcolm Turnbull. Post continues below.

"I have every intention to continue to be vocal on those social and community issues," he said.

"Qantas has always spoken up on gender issues, on LGBTI issues, on Indigenous issues and we will continue to do so and no attempt at bullying us into suppressing our voice will work."

Besides being arrested and attracting international attention, Mr Overheu is also in trouble at home.

He says his wife was furious for actions she said were not consistent with Christianity, while one of his daughters posted a message on social media supporting same-sex marriage but saying "I love my idiot dad".

He has been charged with giving false details to police but he's yet to be charged with the actual "pieing".