WELLINGTON, Nov. 21 (Xinhua) -- New Zealand transport costs went up 17 percent higher in the September quarter as diesel prices increased 11 percent from the previous quarter and the government reinstated full rates for road user charges, according to the latest official statistics Tuesday.

Road freight costs are going up dramatically at a time when the economy is slowing, according to the statistics from the National Road Carriers Association (NRC)'s cost index tool collated by economics consultancy Infometrics.

"There is a real squeeze on margins - we are going to see some trucking businesses under stress," said NRC general manager of policy and advocacy James Smith.

"Upward pressure persisted across most other cost categories, although there are signs the rate of increase has either peaked or is close to doing so," Infometrics chief forecaster Gareth Kiernan said.

Prices for tires fell for the second consecutive quarter, helped by lower international commodity prices and the normalization of supply chains after the disruption since the start of the COVID-19 pandemic, Kiernan said.

Diesel prices have eased slightly from their peak recorded in early October. However, based on data for the quarter to date, diesel prices will be an average of about 8 percent higher in the December quarter than they were in the September quarter, he said.

A continued rise in unemployment towards 5 percent during 2024 should start to translate into slower growth in labor costs and repairs and maintenance costs in coming quarters, Kiernan said.