BP is raising investment and betting its future on oil over gas, as the slimmed-down group fights to recover from the oil spill in the Gulf of Mexico and Russian rows that have hurt both its reputation and its share price.

In a strategy update, it told analysts about plans to raise capital spending, excluding acquisitions, to between $24 billion (£15bn) and $27bn a year in the years 2014 to 2020 from an estimated $22bn in 2012 and $19.1bn in 2011.

Next year and in 2014, spending will average between $24bn and $25bn.

The so-called "upstream" oil and gas production arm of the business that generates the bulk of profits will absorb more of that spending too – 80% up from 70% at present – further reducing the importance of its refining and marketing, trading and other non-production activities.

The extra spend will be financed by higher cashflow from operations and asset sales of between $2bn and $3bn a year.

BP, which is headed by chief executive Bob Dudley, re-affirmed a target it set at the beginning of the year to increase operating cash flow by 50% by 2014 versus 2011.

Like all top investor-owned Western oil firms, BP is struggling to increase output and reserves as nations guard their resource wealth jealously, while also having to spend ever more to find and develop new supplies.

Unlike its peers however, BP has had some difficult recent years in the United States and Russia – which together contribute about half the company's output.

In order to pay its dues for the oil spill and refocus its Russian strategy, BP has undergone a massive rearrangement of assets with total completed and planned divestments of $65bn – about half its total market value.