BP is to invest about £670m to extend the life of its North Sea assets.
BP hopes the investment will secure the future of its Eastern Trough Area Project (ETAP) fields until at least 2030.
Regional president Trevor Garlick said the sector was facing challenges but that the company remained committed to improving competitiveness.
He said the main areas of focus were the west of Shetland and central North Sea.
Mr Garlick said: "These are challenging times for the industry and we are having to make hard choices.
"Nonetheless, we remain committed to improving the competitiveness of the North Sea and to maximising economic recovery from our fields."
He explained: "BP's primary areas of focus are the west of Shetland and central North Sea, where we are investing in both new developments such as Clair Ridge and Quad204, and in extending the life of our mature assets.
"Two weeks ago we welcomed the arrival of the Safe Caledonia flotel into the ETAP area, launching the start of a major investment programme to renew the platform and extend its field life.
"In parallel, we are drilling new wells on ETAP's Machar and Marnock fields, replacing subsea infrastructure, and deploying new technologies to help maximise the fields' recovery.
"ETAP holds significant potential and we are working to ensure its reliability, efficiency and long-term competitiveness. This project will secure the future of the field until 2030 and beyond."
'Encouraging to see'
Industry body Oil and Gas UK's chief executive Deirdre Michie said: "It is encouraging to see the continuing investment BP is making in its North Sea assets and projects to deliver a secure indigenous supply of energy for the country.
"Given the harsh business environment upstream oil and gas companies currently face, with the oil price more than halved since this time last year, industry as a whole is putting a great deal of effort into improving the performance of its assets - and that is something we'll look to explore in further detail in our 2015 Economic Report next month."