Mercedez Harrison was burned by a stray firework. Photo / Dean Purcell

Mercedez Harrison was burned by a stray firework. Photo / Dean Purcell

National Party leader John Key believes a ban on the sale of fireworks is inevitable.

"I'm of the view that what's going to happen is inevitably they will be (banned)," Mr Key said on TV One's Breakfast programme today.

"You can feel that happening in Parliament. Support for fireworks is slipping away."

He personally believed fireworks provided a great deal of fun for families, but the risks associated with them would inexorably lead to a ban.

"You've just got to accept, I guess, that there are some risks with these things and I just think it's inevitable that in the reasonably foreseeable future they will be outlawed."

National's caucus was yet to discuss the issue this year.

His comments came after an incident in which a baby girl was badly burned when a runaway cracker exploded in her pram increased the pressure for a ban on the public sale of fireworks.

Mercedez Harrison suffered burns to 7 per cent of her body after a rogue firework struck her, setting her clothing alight.

Last night her mother, Polly Anne Tonihi, said Parliament should enforce a ban on fireworks - or prepare for more horrific incidents.

"They are just too dangerous. They are not designed for kids, and they're not suitable when the fireworks company is making faulty ones."

Prime Minister Helen Clark also warned last night that "distressing" incidents such as Mercedez's case could tip the balance toward a ban on sales of fireworks to the public.

"Fireworks are dangerous. We have limited sale, we've increased the age at which you can buy them. But at some point, public tolerance for this will boil right over."

She said such cases could lead to a ban on sales of fireworks to the public.

And she added that she was waiting for a report from the Police and Fire Service to see if going to the "next step" was justified.

One-year-old Mercedez was at the top of her Tauranga driveway - 15m away from where fireworks were being lit on the road - when a rogue cracker flew into her pram, igniting her napkin, blanket, and T-shirt.

Her father, Rueben Harrison, who was nearby, said the firework went into a spin and popped as he pulled Mercedez from the pram.

He ripped off her napkin and put the little girl under the shower.