Motorists are being warned of potentially slippery conditions following reports of a possible diesel or oil spill on near the Tauranga Harbour Bridge.

A caller to the 0800 SUNLIVE news hotline says the spill is on the off-ramp coming from the Tauranga Habrour Bridge onto Mirrieless Road.

"It is in the right hand lane.

"It spreads pretty much all the way up the ramp. Local contractors have been advised."

With heavy rain hitting the Tauranga region overnight, slippery conditions are possible on the roads and people are being advised to drive to the conditions.

At the scene?

Call 0800 SUNLIVE or email photos to newsroom@thesun.co.nz