The New Zealand government has bowed to public pressure and added an extra flag design to the four options already being considered for a new national banner.

The so-called ‘Red Peak’ design has generated a groundswell of support since a government committee unveiled its four preferred options this month to a lacklustre public response.

In contrast, more than 50,000 people signed a petition calling for Red Peak’s inclusion in a ballot for a new flag to potentially replace the existing one, which has a British Union Jack in the corner.

• ‘Government must honour these deaths with action’
• Peter Greste’s Al Jazeera colleague pardoned
• This man will likely be the subject of Serial season two

The government initially refused to budge but relented in the face of an intense social media campaign.

“On a matter like this, you would expect New Zealanders to become a little bit passionate, so we have given them another option,” cabinet minister Gerry Brownlee told parliament.

Red Peak consists of red, black and blue triangles with a white chevron.

Designer Aaron Dustin says it contains references to New Zealand’s mountainous terrain and indigenous Maori culture.

Three of the other designs include a silver fern leaf, the informal national emblem which Prime Minister John Key has said he wants on the flag.

The final option depicts a spiralling black-and-white koru, or fern frond, a traditional Maori symbol of new life and creation.

Mr Key has led the push for a new flag, saying the existing one is an outdated relic of British colonial rule and should be replaced with something that “screams New Zealand”.

Kiwis will pick their favourite among the five options in a referendum to be held between November 20 and December 11.

The winning design will then go head-to-head against the existing flag in a second vote in March.

An opinion poll this week showed 69 per cent of people want to keep the current flag.