For diesel, there were 49.9 days’ worth (from 54 days) in total – 27.6 days (25 days) in the country and 22.3 days (29 days) on its way.
For jet fuel, there was a total of 52 days’ worth in stock or on its way (up from 50 days on March 1).
The number of oil tankers transiting the Strait of Hormuz off the Iranian coast has come to a near standstill after the US and Israeli attacks on Iran from February 28.
The strait is a key chokepoint for the global oil trade, facilitating the passage of about 20% of global oil supply.
Around 80% of the crude that passes through the strait is destined for Asian refineries, which supplies New Zealand the petrol, diesel and jet fuel.
Under minimum stockholding obligation (MSO) rules, fuel importers must hold minimum levels of fuel, either onshore or in New Zealand’s exclusive economic zone (EEZ).
The rules state that they must hold 28 days’ cover of petrol, 21 days’ cover of diesel and 24 days’ cover of jet fuel.
The Ministry of Business, Innovation and Employment said it had convened the Fuel Sector Co-ordinating Entity under the National Fuel Plan, which increases oversight of fuel imports and monitors the situation.
On world markets, Brent crude oil last traded at around US$88 a barrel, having hit just under US$120 a barrel earlier in the week.
Jamie Gray is an Auckland-based journalist, covering the financial markets, the primary sector and energy. He joined the Herald in 2011.
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