what the most or best affective weed killer

[manutdstott]

i recently dug between the weeds from between my flags in my back garden, and need to know whats the best or most affective weedkiiler to keep them at bay? and would it help if i cement between the flags?
regards Jason

[wychwood1]

Try Roundup or Pathclear, although cementing would be a more permanent way to get rid of weeds.