Facebook advertisers will be able to opt out of parts of the social networking website following the discovery that some campaigns were running close to content promoting the British National Party, the far-right political party.

Companies including Vodafone, Virgin Media and First Direct, the internet bank owned by HSBC, last week pulled Facebook campaigns after finding these were running next to a page for the BNP. They vowed not to return unless they had reassurances about where their ads appeared.