The Labour Party's "Stop Asset Sales" campaign has hit a red light within days of its launch with National Party ally and blogger David Farrar blowing the whistle on signs that appear to break the road rules.

Labour's campaign features placards based on road "stop" signs but Mr Farrar yesterday posted a photo on his Kiwiblog site showing the signs planted on the median strip of a road in Petone which he said breached road rules.

New Zealand Transport Agency spokesman Andy Knackstedt said based on the photo, "on the face of it they are in contravention of the rules".

Land Transport Rules on Traffic Control Devices state that a person must not install on a road, or in or on a place visible from a road, a sign, device or object that is not a traffic control device; but that may be mistaken for a traffic control device. However, Mr Knackstedt said he was unaware of any complaints to the agency about the signs although policing of the rules was up to the relevant local authorities.

Labour leader Phil Goff, who launched the campaign last week, said he didn't know who within his party had put the signs up, "but if the council has a problem of course they can talk to whoever might have put them out".

While the signs were modelled on stop signs "nobody's going to mistake it as a stop sign, that's just silly".

"This is just the National Party highly embarrassed by the fact that most New Zealanders don't want asset sales and the Labour Party is standing alongside New Zealanders in that view.

"In fact we're leading the push back against the assets sales. That's why they'd love to see us not have the chance to get our message out there.

"We'll keep using those signs. If the council's got a problem we'll listen to them of course, but nobody thinks they're going to be a traffic hazard, that's just nonsense."