You should pull up and remove weeds by hand as and when they appear. If it is a regular problem, you might need to reseal the paving. In extreme cases, the sub layer itself may need to be re-laid. You can use weed killer, however some paving can be discoloured by stronger weed killers.
Ravenglass
Ravenglass is a small seaside town and also all-natural harbour in Cumbria, England about halfway in between Barrow-in-Furness and Whitehaven. Historically in Cumberland, it is the only coastal community in the Lake District National Park. It is located at the tidewater of three rivers: the Esk, Mite as well as Irt. The hamlet of Saltcoats lies north of the River Mite.