It is unlikely that the ram lambs will tup the ewe lambs at this stage. What I would do is wean them the other side of a fence from the ewes and then when they have calmed down, split the ram and ewe lambs. If the ewe lambs are to go back with the ewes, wait a few weeks.
I have tried weaning them a couple of fields away but find the ewes will suddenly jump fences/push under gates etc to get back to the lambs. However, they rarely go in the same field, just to where they can see them. Its as if they want to know the lambs are OK, but dont want them suckling anymore...