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.
Budleigh Salterton
Budleigh Salterton is a small town on the shore in East Devon, England, 15 miles (24 kilometres) south-east of Exeter. The community exists within the East Devon Area of Outstanding Natural Beauty. It creates a huge part of the electoral ward of Budleigh, whose ward populace at the 2011 census was 5,967. Budleigh Salterton lies at the mouth of the River Otter, where the estuary forms a location of reed bed and also grazing marsh. This creates an essential sanctuary for migratory birds and a Site of Special Scientific Interest for those thinking about bird seeing. It has a marked area for naturists. Budleigh Salterton lies on the South West Coast Path, with clifftop paths eastwards to Sidmouth as well as westwards to Exmouth. The pebble beach as well as cliffs belong to the Jurassic Coast World Heritage site.