The company informed staff of its decision yesterday and has begun a consultation process on the issue.
BP proposes bringing in the changes from next January, when staff would move from their current two-weeks-on, three-weeks-off rota to the new working pattern.
It said the move would deliver “material, long-term cost savings” to its UK offshore business, as well as reducing logistical risk, providing better operational continuity and increasing operating efficiency.
The issue of any potential redundancies would be explored as part of a separate consultation.
A BP spokesman said: “Across BP we are looking at a range of measures to make our business more competitive for the long term.
“In the North Sea, we believe that a key step toward this is to review our UK offshore rotational arrangements. We spoke to employee representatives yesterday about our decision to move to a 3/3 rota.
“We are committed to full and open consultation with our employee consultation and communication forum and also to ensuring that safe operations remain our number one priority by conducting a thorough risk assessment.”
The company said it has taken the decision within the context of a “sustained and challenging business environment” and that it is one of a range of measures being looked at to make the business more competitive.
BP reported a 20% drop in first-quarter profits last month after it was hit by a sharp slump in oil and gas prices.
The energy giant said underlying replacement cost profit fell to 2.6 billion US dollars (£1.7 billion) from 3.2 billion US dollars (£2.1 billion) in the same period last year.