Police could soon have the power to prosecute window washers on some of Christchurch's busiest intersections.

The Christchurch City Council will decide on Thursday whether police can seize equipment and prosecute on its behalf under the authority of local bylaws.

Councillor David East said there's two main issues they need to deal with when it comes to window washers.

"My primary issue would be from the Health and Safety point of view and then dealing with the allegations of gang association is probably the secondary issue that we are dealing with."

East said it's not a new issue but they've got to deal with the health and safety aspect, and can't have them weaving in and out of traffic on busy intersections.

"There probably some window washers that are probably quite safe in their operation, but like a lot of things I suppose it's when a minority cause some issues we have to deal with the wider problem."