A press officer who joked the best way to support Streatham High Road would involve a substance used in chemical warfare has left his job.

Sam Masters, who was paid by Lambeth Council to promote the borough, left on Friday after the remarks posted on the social networking site Twitter provoked outrage amongst business leaders, politicians and residents.

The comment, posted on a Twitter account which has since been deleted, read: “Having spent a considerable amount of time in Streatham, my solutions for supporting the High Road mostly involve napalm.”

In a letter to the Streatham Guardian, the former south London journalist later apologised for the remark, saying he was “genuinely sorry” for what he saw as a “silly joke”.

The council insisted today he had taken the decision to leave the local authority, but had neither been sacked nor resigned.

A spokesman said: “Sam was a freelancer on a daily rate and has chosen to pursue other opportunities.”

Last week, chair of the Streatham Business Board, Lee Alley said he was planning to lodge a formal complaint with the council over Mr Master’s comments.