The Government will today bow to public pressure and allow hundreds more Syrian refugees to seek sanctuary in New Zealand.

In response to the worst humanitarian crisis since World War Two, Prime Minister John Key will seek approval from Cabinet to open the borders and resettle more asylum seekers.

Prime Minister John Key will seek backing from Cabinet today in response to the Syrian refugee crisis. Photo: File.

No figure has yet been decided but it's understood the one-off emergency intake - perhaps up to 500 - will occur over a period of three years.

Key is also set to announce more humanitarian aid, on top of $15m already committed, to refugee camps in the Middle East.

A senior Government source said: 'Cabinet will make a decision to bring in more Syrian refugees over and above the normal refugee quota, and provide additional financial aid for the region.”

National wants to ensure refugee services can cope with the extra influx, which will put additional pressure on housing. It's also understood a shortage of translators makes a gradual intake necessary.

A review of the annual quota - currently at 750 - will take place next year as planned.

Calls for New Zealand to do more intensified after drowned three-year-old Syrian boy Aylan Kurdi washed up on a Turkish beach last week.

Key found himself on the wrong side of a public backlash after refusing to act until next year's review. Amnesty, the United Nations, Catholic bishops, former Prime Minister Helen Clark and local mayors publicly urged the Government to do more.

Almost 3000 people pledged to open their homes and holiday houses to asylum seekers, signing up to a Facebook page.

Labour and the Greens are to table legislation next week in response to the crisis. Labour's bill allows for an extra 750 Syrians in immediate response to the crisis. The Greens' measure will lift the quota permanently to 1000.

The Government source acknowledged today's announcement might not be enough to see Opposition parties back down. But neither bill is likely to succeed as National has already indicated it will deny leave.

Labour leader Andrew Little said New Zealand must "play our part alongside many other countries to alleviate this crisis."

Kiwis have a "track record" of opening up borders to help. "There is something in our nature - we are people of conscience and compassion - to offer help and do something about it."

For Labour to consider dropping their bill, the Government's announcement must be "material", he said.

"Another 100 or even 200, given the magnitude of the crisis, is going to leave people disappointed. It would leave me disappointed. This is not a time to be grudging in our generosity," Little said.

"Another 750 over the course of next year might be a drop in the ocean to the problem in Syria, but it's a significant contribution on our part."

Over the weekend, both Britain and Australia indicated they will accept more refugees fleeing the war in Syria. Prime Minister Tony Abbott would not commit to a specific figure but said it would be "significant" and more than the 4400 resettled last year.

Meanwhile, Key responded to reports that France was preparing to launch airstrikes on Islamic State targets in Syria.

"That's a matter for the French government," a spokeswoman said. "New Zealand's contribution is limited to capacity building in Iraq and we are not considering any additional deployments to the anti-ISIL coalition at this stage."