Tanzania has directed bulk petroleum importers and suppliers from its northern regions to use the Tanga port instead of Dar es Salaam.
This is expected to result in lower pump prices in Kilimanjaro, Arusha and Manyara areas.
Petroleum product importers and suppliers in northern Tanzania however say the Dar es Salaam port is more efficient than Tanga.
The new directive comes less than a year after Energy Minister Medard Kalemani ordered petroleum suppliers in southern Tanzania to use the southern port of Mtwara.
Tanga port is now under expansion to increase its depth from the current 3.5 metres to 15 metres after a feasibility study for dredging the port was finalised last year. Dredging will increase the port's handling capacity to one million tonnes per year.
Tanga port has been earmarked for Ugandan petroleum product importers and other cargo going to Kampala through Tanzania.
A Ugandan oil and gas delegation visited the port last November to assess the cost effectiveness and cargo handling facilities.
The government had encouraged bulk oil importers and suppliers to construct more oil storage facilities at Tanga.
The Tanzania Port Authority is planning to develop a modern jetty at the Raskazone oil terminal in Tanga port that can accommodate medium-sized oil tankers of 80,000 to 120,000 tonnes.