New Zealand's Finance Minister Nicola Willis has firmly ruled out reducing road user charges (RUCs) for diesel vehicle owners, despite skyrocketing diesel prices triggered by the Middle East conflict.

The decision comes as diesel costs have surged to match 91 unleaded petrol, with the added burden of RUCs making diesel vehicles significantly more expensive to operate than petrol counterparts.

In an interview with RNZ, Willis expressed sympathy for affected diesel users, noting the global disruptions hitting diesel hardest. "I have deep sympathy for diesel users because diesel is the fuel globally that has been most disrupted by the Middle East conflict," she said.

However, she emphasized that any RUC reduction would fail key tests of being "temporary, timely, or targeted," potentially benefiting higher-income and high-fuel users disproportionately while undermining efforts to reduce overall fuel consumption.

Willis underscored New Zealand's "fairness principle," where all road users contribute equally to road maintenance, petrol via excise tax and diesel via RUCs. "If we were to do something for diesel users, petrol users would fairly ask why they're not getting it," she explained. 

She acknowledged the hardship on families, firms, contractors, and agricultural businesses but prioritized alternative supports, such as income supplements for low-income families with young children.

Instead of tax cuts, the government's focus remains on securing diesel supply and contributing to global stabilization efforts.This stance aligns with broader energy conservation calls amid New Zealand's vulnerability as the "last stop on the global supply chain for oil and diesel," as noted in related commentary.

The announcement highlights tensions in New Zealand's transport policy as fuel crises intensify, with economists warning of worsening shortages.