Earlier this month, Newstalk ZB presenter Heather du Plessis-Allan told her listeners it was not worth the expense of sending the PM to the Pacific Islands Forum in Nauru.
"The Pacific Islands wants money from us," she said.
"The Pacific Islands don't matter. They are nothing but leeches on us."
Her comments were posted on social media, prompting lots of angry reactions and some abusive and offensive putdowns of the broadcaster herself.
Williams posted on Twitter last night that he was "disheartened" by the "bigoted" comments.
"I don’t [sic] care what the "context" was - calling Polynesians 'LEECHES' is not okay - period," he wrote.
Williams' response is the latest among New Zealand stars' criticising Ms du Plessis-Allan, actor Sam Neill last week also made his thoughts clear on Twitter after the heated debate became a hot topic.
"How far can you take offensiveness and utter stupidity?" he wrote.
Samoan-born New Zealand writer, actor and Sunday News columnist Oscar Kightley also said Newstalk ZB "owes our Pasifika neighbours an apology".
Ms du Plessis-Allan later invited Privacy Commissioner John Edwards onto her show to debate the issue. He declined and she hit out.
"Go back to university and do some more training. You are not good enough."
She said Mr Edwards' reaction was symptomatic of intolerance on the political left.
"They are like all deep-thinking and progressive but the moment someone says something that they don't want to see the nuance in, they just take the broad brushstrokes of something."
Ms du Plessis-Allan also insisted on air that she had not "dehumanised" or insulted anyone, she had commented only on Pacific Islands' governments.
"I will double down on this. I do not regret what I said because I was not talking about people living in this country or the people themselves. I was talking about the Pacific Islands and the people who run it [sic]," she said.
TVNZ's long-serving Pacific affairs reporter Barbara Dreaver was in Nauru for the Pacific Islands Forum last week when Ms du Plessis-Allan called the Pacific Islands "leeches" on air.
"Now that the phosphate dust has settled and the shameless self-promoting headlines about the Pacific being 'leeches' and a waste of time and money have lost their hysterical edge - let's take a look at some facts," she wrote on the TVNZ website this week.
"New Zealand needs the Pacific as much as the Pacific needs New Zealand," Ms Dreaver said.