Rental agreement law in a joint ownership

My younger brother and I jointly own a 2 floor property (where only the first floor has a registry under both our names.) I live in the 2nd floor and my brother does not live here so he has kept a tenant in the first floor for more than 1 year on rental agreement without our signatures. In the beginning we didn't mind him keeping a tenant because we thought it will help him with some earnings so we agreed verbally on it. But now we want the tenant out. can we do that?