Rig builder Transocean said in its latest fleet status update report that it plans to dismantle four of its offshore drilling rigs.

The company said it plans to scrap the Deepwater Expedition, Transocean Legend, Transocean Rather, and GSF Arctic III "in an environmentally responsible manner."

The steady decline in crude oil prices has forced most major oil and gas companies to cut back on spending in exploration and production, leading in turn to a decline in the volume of rig activity.

In its latest report on global rig activity, oil services company Baker Hughes said deployment worldwide in February was down 66 from the 1,341 reported during the same month last year.

Of the four rigs slated for scrap, only Transocean Legend was active this year. It was last leased by ConocoPhillips for exploration off the coast of Australia, with a day rate of $415,000.

"These rigs are classified as held for sale," the rig company, which has headquarters in Switzerland, said in a statement Wednesday. "As a result, the company expects its first quarter 2015 results to include an estimated non-cash charge of $300 million to $325 million, net of taxes."

Counting the four rigs slated for scrap, the company said it's scheduled a total of 16 offshore rigs for demolition.