Plans by Statoil to modify West Epsilon have been shelved, which means the rig is likely to face a break from drilling in the summer.
"After a financial assessment, we've decided that the modifications needed to use this unit for exploration drilling can't be justified," says Mads Grinrød, vice president for drilling and well technology.
Owned by Smedvig of Stavanger, West Epsilon is currently drilling wells on Statoil's Sleipner fields in the Norwegian North Sea.
However, that work will be completed during the summer. The rig is likely to remain deployed on the field.
Mr Grinrød cannot indicate how long West Epsilon will stay idle.
"It'll depend on the outcome of discussions we're having with the Sleipner licence about using this unit, but we hope the rig can come back into operation during 2000."