New Zealand MP turned gay marriage champion and internet sensation Maurice Williamson could soon add "Hollywood talkshow guest" to his resume after he was given approval to appear on Ellen Degeneres' show.

The 62-year-old National MP, whose staid portfolios include building and construction, customs, statistics and land information, lit up parliament last week when describing why he supported marriage equality legislation, which passed its final reading by 77 conscience votes to 44.

"The most enormous big gay rainbow" rose over his Auckland electorate that morning and he had taken it as a sign to back the change, despite critics writing to him warning he would burn in hell, he said.

He mocked those predicting a "gay onslaught".

"We are really struggling to know what the gay onslaught will look like ... We don't know if it will come down the Pakuranga Highway as a series of troops or whether it will be a gas that floats in over the electorate and locks us all in."

The speech has been viewed more than a million times on YouTube and drawn support from celebrities including Stephen Fry, Ronan Keating and Degeneres, who invited him on her US TV show.

However, he had to decline because parliament's rules could not have them pay for his flights.

But on Monday morning, Prime Minister John Key told Newstalk ZB he had approved Mr Williamson's appearance on the show, but he will have to donate any fee to charity.

Mr Williamson tweeted that he would love to be a guest "if it can be arranged".

"(Degeneres) is awesome - a real inspiration to us all."

Mr Williamson, who is married with three adopted children and describes himself as a "strong right-winger" on economic issues, became an unlikely face of the marriage equality movement, alongside fellow Nats Paul Hutchison and Chris Auchinvole.

 

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