Petrol back near $3.50 a litre, and the AA says relief may not come until Christmas

On the West Coast, 91 petrol already costs more than $3.50 a litre. Most of the country is close behind.

Gaspy data reported by 1News on 25 September put the national average for 91 at $3.40 a litre on 24 September. On 1 September it was $3.01, so the average rose 39c in just over three weeks. Every region was above $3.30 by 24 September. At the start of the month, only the West Coast had been above $3.10.

All price figures here are Gaspy averages; other national averages published in September used different data and won't match exactly.

For a household that fills a 50-litre tank once a week, the September rise adds about $19.50 a fill. That tank cost $150.50 at the 1 September average and $170 at the 24 September average. Over a month, that's close to $80 extra.

The West Coast had the smallest rise, 29c, but stayed the dearest place to fill up at $3.51 a litre, or $175.50 for 50 litres. It was the only region above $3.50. Gisborne rose 43c to $3.47 and went from the fifth-most expensive region to the second.

Nelson rose fastest. Its average went from $2.85 to $3.31, up 46c or about 16%, and a 50-litre fill there now costs $165.50.

On 19 September Nelson also had the biggest one-day jump of any region, more than 7c.

Bay of Plenty rose 44c, Auckland 40c to $3.35, and Marlborough and Tasman about 40c each. Auckland was still the cheapest of the main centres, at $167.50 for a 50-litre fill.

The latest rise comes from overseas. According to 1News, the Strait of Hormuz is closed. Saudi Arabia then shut its East-West oil pipeline, a route that goes around the strait, after drones struck it. The attack was blamed on Iran-backed militias in Iraq. Yemen's Houthi rebels have seized an island that gives them more power to disrupt shipping through the Bab al-Mandab Strait, which carries around 7% of the world's oil. As of 25 September, Brent crude was around US$102 a barrel, 1News reported.

AA principal policy adviser Terry Collins told 1News he could not see relief coming until around the US midterm elections in November, "and maybe even out to Christmas". He also said he did not expect prices to go back to the highs of April and May, when petrol reached about $3.50 a litre in some places.

But on 24 September the West Coast was already at $3.51.