Prime Minister Jacinda Ardern will seek reassurances from UK Prime Minister Theresa May that New Zealand's trade position will be no worse off because of Brexit when they meet in London next week.

Ardern will also attend the World Economic Forum in Davos, where she will join Prince William in a panel discussion about mental health - an area where there is a high expectation of Government action this year.

She will use the trip to London, Switzerland and Brussels to push for free trade agreements with the UK and European Union and promote the Government's Well-being Budget, which will be delivered this year.

"My visit to the UK is an opportunity to underline New Zealand's position as a natural and long-standing partner for the country as it redefines its global role post-Brexit," Ardern said in a statement.

While the UK Parliament voted down May's proposed Brexit deal yesterday (NZT), May survived a no-confidence motion this morning and remains determined to see through a solution that upholds the result of the Brexit referendum in 2016.

The UK has just over 70 days to hammer out a new deal or face a "hard Brexit" – whereby the UK would be completely cut out of the EU and its single market, but have more control over its own borders.

Finance Minister Grant Robertson, who will attend the World Economic Forum with Ardern, said yesterday that the Government was helping NZ exporters prepare for "all eventualities".

"All we can do is make sure New Zealand is prepared for whatever outcome comes from the year – that's what the Government has been doing for some time.

"The thing we can control is the way in which our relationships work with both the UK and the remainder of the EU."

Ardern's main focus will be a free trade deal with Europe, and in Brussels she will meet with European Council president Donald Tusk, European Commission president Jean Claude Juncker and Nato secretary general Jens Stoltenberg.

In Davos, she will promote the world's first wellbeing Budget, which the Government will deliver in May this year.

She will also take part in panel discussions on wellbeing and "options beyond GDP" with the head of the OECD, the future of the international trade with the head of the WTO, and a panel focused on mental health with Prince William.

"Our wellbeing approach is generating significant international interest, particularly at a time when the international rules-based order is under strain and leaders are grappling with constituencies dissatisfied with the status quo.

"I hope other leaders will come to see more compassionate domestic policy settings as a compelling alternative to the false promise of protectionism and isolation."

At the UN general assembly last year, Ardern talked about the importance of a rules-based, multilateral global system in a speech that contrasted starkly with US President Donald Trump's speech, which centred on protectionism.

Robertson will deliver the opening remarks at the World Economic Forum's main Asia-Pacific event - a discussion on bridging the demographic divide.

He will also have bilateral meetings with ministerial counterparts from Singapore, Denmark, France, Canada, Ireland and Chile.

He will visit Brussels, where he will meet with EU commissioners and members of the European Parliament, and the UK, where he will give a speech at the London School of Economics on the wellbeing Budget.

"This is a very timely trip given the dynamic global economic situation," Robertson said.

"While the New Zealand economy continues its stable growth, as international risks mount we must continue to engage with global partners so we are in the best position to address any issues."