United Nations Secretary-General Ban Ki-moon called again for an on-the-ground investigation into the use of chemical weapons in Syria and asked Damascus to grant a U.N. team long-sought access . NEW : Al Qaeda in Syria leader joins rebel al - Nusra Front part of joint operation . Russia breaks diplomatic ties with Syria . Britain says more intervention ` ` should be done on our own timeline , '' British leader says . Russia warns the US against a no - fly zone over Syria .
NEW : Al Qaeda in Syria leader joins rebel al - Nusra Front part of joint operation . Russia breaks diplomatic ties with Syria . Britain says more intervention ` ` should be done on our own timeline , '' British leader says . Russia warns the US against a no - fly zone over Syria .