In 1968, the Nuclear Non-Proliferation Treaty requiring nations posessing nuclear weapons not to help other states acquire them.
Ntwanano lowu, lowu amukeriweke ximfumo hi 1968, wu yirisa ku endliwa ka matlhari ya nyutliya ematikweni lama nga riki na wona ni ku sivela matiko lawa ma nga na wona leswaku ma nga wa endli hi vunyingi.