Statistics New Zealand figures, released yesterday, showed the current account deficit narrowed in the three months ended December to $2.8billion from $4.8billion in September.
The deficit was still larger than expected, leading to a widening of the annual deficit to 2.7% of GDP from a revised 2.5%.
ANZ economist Miles Workman said despite the small surprise in yesterday's release, the deficit remained well below its historical average of 3.6% of GDP.
In seasonally adjusted terms, the current account deficit widened by $400million to $2billion.
The widening was driven entirely by a widening goods deficit to $500million from $100million in September. Strong imports offset a solid rise in exports.
However, Mr Workman said the external imbalances were acting as a greater constraint on growth that was widely appreciated.
''This may sound surprising, given both the current account deficit and external balance sheet are far healthier than is typical at this point in the cycle.
''But with more regulator and credit rating agency scrutiny over external borrowing, more onus is falling on saving to fund domestic development.''
In the year to March, national saving rose to 8.8% of disposable income - the highest since 2004.
It was a theme the ANZ saw continuing, he said.
Typically, more saving meant less growth.
ASB chief economist Nick Tuffley said New Zealand's external accounts were ''largely stable''.
''While quarter four showed a widening in the current account balance, we expect this is likely to prove temporary.''
This year, the current account deficit was expected to narrow.
In particular, New Zealand's goods terms of trade now sat at a record high, he said.
In addition, tourism exports were likely to remain firm, while the country's agricultural production and exports were likely to improve this year following a poor growing season.
''While this remains our central view, risks have grown to this outlook. Namely, a possible US-initiated trade war could counter this view.
''Indeed, while New Zealand is not in the direct firing line of [United States] President Donald Trump's recent tariff increases, in the event of a trade war everyone loses, including New Zealand.''
Mr Workman said there were no obvious implication from the balance of payments data for the GDP figures due out today.
Slightly stronger than expected goods imports were likely to see net exports drag on growth.
