His ‘big gay rainbow’ speech was played on the show last week after it went viral online.
Normally politicians are not allowed to take up the offer of a paid trip, but Prime Minister John Key told TV One's Breakfast this morning that Williamson "can absolutely go".
"Anyone who has seen Maurice speak before, the good people of Pakuranga, will know what I'm talking about, he is very funny."
"He is ferociously bright, he's always had that incredibly witty sense of humour and I don't think that he did an awful lot of planning for that speech."
Key says any payment the MP gets for the appearance will go to charity.
YouTube clips of Williamson's speech have hit 15 million views.