This morning saw the first radio London mayoral debate of the campaign on LBC. When these events are reviewed, they usually fill space with descriptions of candidates going ‘toe-to-toe on bus fares’ or ‘clashing over affordable housing’. Well, no need for hyperbole today. The debate was dominated by issues such as housing, crime and transport, but it was what happened after the debate that is likely to grab headlines.

Taking affront to accusations from rival Ken Livingstone of improper tax arrangements, Boris Johnson made his feelings known as the two squeezed into a lift after the debate. According to tweets from Simon Harris of ITV News, Boris’ face was ‘red with rage’ as he and Ken went ‘nose-to-nose’. Remove the expletives from their conversation, and the gist is that the Conservative candidate rather forthrightly accused his opponent of lying. You can find lots of colour on the exchange at the Guardian.

Aggressively accusing his rival of lying in a squeezed lift may not be archetypal mayoral behaviour, but Johnson could do his chances of retaining the position a great deal of good by playing into Londoners’ wider ambiguity over Livingstone. The early signs are this is just what he intends to do, with the mayor’s office releasing a statement claiming “This is his (Livingstone’s) last chance to be Mayor and he will do and say anything to get elected.”

The polls are tight, and there remains sufficient time and space for a candidate to seize the debate. If Johnson can make this election about trust, Livingstone could suffer. Does today's stand-off in the LBC lift reveal this will be a particularly bad-tempered contest?