He then accused them of being "Islam c***s" and told them to "go back to your own country".
Pene Walker, 60, who was a passenger on the bus, stood up for the young men and called out "welcome to New Zealand" to them before telling Tupaea to behave himself.
Tupaea then repeatedly told Ms Walker to "shut your mouth up b****".
Speaking outside court this morning, Tupaea said he was sorry to the young men involved.
"It just came out I'm sorry about that," he said. "I am not a racist man."
He also apologised to Ms Walker.
"I would like to see her to clear everything up and say sorry for everything."
Tupaea said this was the first time -- and last time -- he would have an "outburst" like this on a bus.
Ms Walker said she was pleased that Tupaea had pleaded guilty so things "didn't have to go any further" and was unsure as to whether she would sit down and speak to him following the outburst.
She described Tupaea's actions on the bus as "vicious".
Wellington police Maori responsiveness manager Inspector Tracey Thompson thanked members of the public who helped with the police investigation.
She said following the incident, Wellington police continued to reinforce that abusive behaviour was not acceptable in the community.
"Everyone in our community has the right to be safe, and feel safe as they go about their daily business."
Tupaea was remanded at large until his next appearance in May.
