Kevin Watkins' article linking RBS to tar sands developments in Canada was highly misleading and ignored the billions of financing RBS has provided to renewable power projects (A fund for climate chaos, 5 March).

Watkins states: "Since recapitalisation, [RBS] has been bankrolling some of the world's most ecologically destructive investments. RBS is a global leader in underwriting loans for companies such as Shell and Conoco Philips, exploiting oil tar sands in Canada's Alberta province. Detailed analysis by People and Planet, the environmental organisation, documents a tar sand portfolio that has grown by $2.7bn since the government bailout."

We carefully assess the environmental credentials of the companies we do business with. RBS has no such portfolio and has not provided any finance directly to tar sands projects in the last three years – contrary to Watkins' assertion that large parts of our energy financing go directly to tar sands. Watkins also states that RBS's record in this area is an "open and shut case" – a surprising claim given his lack of discussion with us or consideration of our role in renewables financing.

Watkins declares that "RBS could be gearing its lending towards support for a low carbon transition strategy for Britain". If he had investigated further he would have found that over the past five years we have been ranked consistently in the top five lenders globally to renewables, well ahead of any other UK bank.

In response to Watkins claim that RBS is "subverting national policies on climate change", I want to make it completely clear that RBS fully understands the problem and we are contributing to the solution. Since 1998 we have financed over 8,800MW of wind generation globally – more than twice the total installed UK wind generation capacity.

At the end of last year, we were chosen as one of three banks to participate in a wind financing scheme backed by the European Investment Bank that will make up to £1.4bn available to onshore wind power projects in the UK over the next three years. These are not the actions of a bank intent on "funding climate chaos", as Watkins puts it.

But there are other issues to contend with. If we could treble our renewables financing overnight, we would. Unfortunately there are just not enough viable projects needing finance because of issues over planning, grid connections, cost and technology risks. We are closely involved in helping to remove these barriers, as highlighted in our submission to the recent Environmental Audit Committee.

The reality is that, whether we like it or not, our society is currently dependent on hydrocarbons. The transition away from them will require co-operation between governments, power companies, local communities and ultimately the end consumer. We are determined to play our part but oversimplification of the issues will take us nowhere.