Chief executive Ben van Beurden outlined his view on the North Sea as Shell unveiled a 23% fall in full-year profits, excluding identified items, to $19.5 billion for 2013.
The results include a difficult fourth quarter for Shell, as trailed in a profits warning - its first since 2004 - two weeks ago.
Shell cited higher depreciation, increased exploration costs, lower upstream volumes and weak industry conditions in downstream oil products as fourth quarter earnings came in at $2.9bn before identified items. This compared with $5.6bn in 2012.
The fourth quarter earnings included a net charge of $763m brought by costs linked to shale properties, gas infrastructure and a drilling rig in the US.
It also reflected restructuring and redundancy costs.
The results came as Mr van Beurden, who succeeded Peter Voser as chief executive last summer, wasted no time in stamping his mark on the business, by putting the brakes on Shell's controversial plans to drill in offshore Alaska.
A US court recently ruled the Department of the Interior had not fully considered the environmental impact of the drilling, which Shell said had raised "substantial obstacles".
And in a further example of the changing landscape facing the company, Mr van Beurden declared Shell would reduce its exposure to the "complex" security situation in Nigeria.
Speaking to investors, Mr van Beurden said the company planned to increase the pace of asset sales to streamline its portfolio, and expects to generate $15bn across its upstream and downstream operations in 2015.
There has been speculation following the profit warning that Shell could move to sell off assets in areas such as the North Sea to try and boost returns.
Mr van Beurden refused to rule this out in the long-term, given the maturity of some assets. But he emphasised the importance of the North Sea in the meantime, citing the "significant investment" it has in assets such as Clair and Schiehallion west of Shetland.
Mr van Beurden said: "The North Sea is no exception to the rule - there are no reasons for us to take a different view to any part of our portfolio.
"It will be a matter of us looking at all the different components and just asking ourselves: are they still sufficiently attractive and resilient to keep in our portfolio?
"And if they have run out of run length, which will be the case, of course, eventually for all upstream assets, the discussion is: is this asset better owned by somebody else? There is no reason why we should have a different approach to the North Sea.
"But at the same time I also want to make sure that we see lots of opportunity in the North Sea."
On Alaska, Mr van Beurden said he was disappointed to scrap the plans, but noted "the lack of a clear path forward means that I am not prepared to commit further resources for drilling in Alaska in 2014."
He pledged to reduce capital spending, from $46bn in 2013 to $37bn this year, and said Shell "will no longer be updating against previous cash flow and net spending targets". He said: "I want Shell to be measured on our competitive performance."
Analyst Cannacord Genuity, which reiterated its recommendation to buy with a target of 2650p, was sceptical about the move. It told investors: "The fact it will no longer measure itself against these targets could be seen as an admission of failure.
"The refocusing on improving financial results, capital efficiency, operational performance and project delivery are all welcome, but we believe the market will need to see to clear milestones before buying fully into the new programme."
Royal Dutch Shell A shares closed up 22p at 2147.50p.