Duncan Garner has decided to quit Twitter after being subjected to "abusive and violent" tweets over the weekend.

On Saturday, Fairfax published a column he wrote, called: 'Dear NZ, how do we want to look in 20 years?'

Garner regaled readers with a tale of going to Kmart to buy some undies and seeing a "human snake" at a self-service counter made up largely of "Indians, Pakistanis, Sri Lankans, Syrians".

He used that "snake" as the basis of an argument that New Zealand is at risk of becoming "an international cot case of broken cities, poor planning, congested highways and stolen dreams" if issues like immigration and infrastructure planning aren't dealt with properly.

But many on social media site Twitter disagreed with the host of Three's The AM Show.

"Kmart needs to ban Duncan Garner, mate go get your undies at the warehouse," wrote @timtoez09.

"Duncan Garner drives his made in Japan car to buy made in India socks goes home to write racist shit on his built by China computer," said @LucyZee_.