National Party leader Todd Muller has doubled-down on his decision to take a controversial Make America Great Again cap to his new office in Parliament.

A Muslim community leader said today the cap should be left at home as it represents something very different from when Muller bought it as a souvenir in 2016, as well as two Hillary Clinton pins.

Aliya Danzeisen of the Islamic Women's Council said the MAGA cap had no place being displayed in a Parliamentary office.

"That hat represents the denial of the freedom of beliefs. That hat represents the denial of minority voices. That hat represents the vitriol that has been harming that nation and has been harming the world for the last four years," Danzeisen said.

"If he wants to be the Prime Minister of New Zealand it would be nice if he'd choose to display objects that represent the values of New Zealand."

But Muller today doubled-down on his decision to display the hat, saying he feels "very comfortable" including it in his collection of political paraphernalia.

Muller, a US politics nut, got the MAGA hat in 2016 when he went to watch the Democratic and Republican campaigns.

Muller said he hoped people could understand he displayed the cap in the context of a number of other political souvenirs.

"I would hope that they could understand the context in which it was there because I think context is important for a lot of things, actually. Clearly he's a very divisive individual and a lot of people are reacting because they're assuming that it means something which clearly it doesn't."

She invited Muller to sit down with her so they could have a conversation about what the MAGA hat now represents.

"It doesn't just mean a trip to America it now means a lot more for a lot of people."

Danzeisen said she didn't think Muller "fully thought it through" and asked him to reconsider his decision to take it with him to Parliament.

She said if it was just a personal memento of his travels, then it shouldn't be put on a prominent shelf and should instead stay at home. There were "more productive" things he could display.

The cap has become the centre of controversy online. People have slammed it as inappropriate but also defended Muller's position on it.