Shell is to cut 250 jobs in its North Sea operations and introduce changes to shift patterns, the company has announced.
The oil giant said the plans will affect staff and agency contractors and were part of a range of initiatives to manage costs and improve the competitive performance of its operations around the world.
Staff and agency contractors based in Aberdeen and on installations in the North Sea were told of the plans during a meeting today.
"The North Sea has been a challenging operating environment for some time. Reforms to the fiscal regime announced in the Budget are a step in the right direction, but the industry must redouble its efforts to tackle costs and improve profitability if the North Sea is to continue to attract investment," Paul Goodfellow, Shell's upstream vice president for the UK and Ireland, said.
"Current market conditions make it even more important that we ensure our business is competitive. Changes are vital if it is to be sustainable. They will be implemented without compromising our commitment to the safety of our people and the integrity of our assets."
The cuts are in addition to 250 job losses announced last August.
Shell employs around 2,400 staff and agency contractors in its North Sea business, but that figure will fall by the end of the year after the two job loss announcements.
The current shift pattern is for two weeks on, two weeks off, two weeks on, four weeks off.
One of the options for changing the system is for three shifts on, three shifts off.
The GMB union said it was "miles apart" from the company after talks on pay, staffing levels, changes to rosters and holiday arrangements.
National officer David Hulse said the union will get the results tomorrow of a consultative ballot among members, adding: " Unilateral action by employers will make matters worse."
Chancellor George Osborne announced major changes to the North Sea tax regime in his Budget last week, in response to difficulties facing the UK oil and gas sector.
He said Petroleum Revenue Tax would be cut from 50% to 35% to support continued production in older fields.
The existing supplementary charge for oil companies will also be cut from 30% to 20%, backdated to January.