David Cameron has intervened over the BBC plan to axe his constituency's local news service as part of the latest round of cost-cutting at the corporation.

The BBC has been looking at axing the three regional "sub-opt" services that provide news for Oxford, Cambridge and the Channel Islands as part of the corporation-wide Delivering Quality First review aimed at saving more than £400m.

According to sources, BBC director general Mark Thompson – who also lives in Oxfordshire – received a letter indicating Cameron's displeasure. Cameron represents the west Oxfordshire constituency of Witney.

BBC insiders confirmed that the three regional opt-outs in Cambridge, Oxford and the Channel Islands will not be axed but said the corporation had already decided not to proceed with the idea before Cameron wrote to Thompson.

Cameron's letter arrived just a few days after a big two-day BBC summit about DQF on 12 and 13 May.

A BBC source said: "The director general was happy to reassure those concerned, and confirmed that these local services will not be axed."

In a letter replying to Cameron, Thompson said: "We have decided to approach the challenge of planning the BBC's future in as open way as we can, listening to our audiences and involving as many people inside the BBC as possible in debating the opportunities, choices and challenges we face.

"As a result many different ideas have been raised. I believe it is right to have such an open debate but an inevitable consequence is that ideas will surface which do not make sense or which run contrary to the BBC's fundamental public purposes.

Thompson went on: "Your constituents are correct that there has been a suggestion from some of my colleagues that, in order to save money, we should withdraw those regional services – based in Cambridge, Oxford and the Channel Islands – which serve the smallest populations.

"Like you however, I believe that these services are very valuable, particularly in the light of ITV's retreat from regional broadcasting, and that to withdraw them would be a retrograde step. I do not intend to include this idea in the final package of proposals that I submit to the BBC Trust."

Cameron told local television station Witney TV he had "good news" about the proposed cuts to BBC Oxford.

When asked by reporter Barry Clack from Witney TV, "as the prime minister is there anything you can do to stop [the cuts] happening?", Cameron responded: "I've got good news here in that I was very concerned about what was being proposed. Obviously the BBC has got to make spending reductions like everybody else but actually I think local news is incredibly important.

"They do provide a good service here in Oxfordshire and I think they are going to be going on doing that and we're still going to have the separate Oxford news on the BBC, which I think is absolutely great."

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