The council has vowed to banish the technical problems which have troubled the new Sullom Voe tugs since their delayed delivery to the isles last year.
The Solan and Bonxie, which cost the council £14 million, have been out of action because of severe steering and stability problems.
In one incident last winter, the Solan lost power and was struck by the oil tanker Loch Rannoch in the middle of a towing operation.
This morning’s harbour board met in private to discuss a report on the Spanish-built vessels, which have now been tied up for over six months.
In a statement after the meeting, head of infrastructure Phil Crossland insisted the SIC would take appropriate “technical and professional” advice to help solve the issues.
A review of the project will also be carried out, involving crews and staff from Sella Ness.
Mr Crossland refused to give a timescale for the review, adding the immediate priority was to fix the technical glitches that have troubled the vessels.
He said: “The report was an up-date on the directional stability issue we have with the vessels.
“We are taking technical and professional advice to resolve the situation and get the tugs back in service as soon as possible.
“The board recognised we need to do a review of the project at the appropriate time, but the priority at the moment is to solve the problem.”