The <a href="https://en.wikipedia.org/wiki/Treaty_on_the_Non-Proliferation_of_Nuclear_Weapons" id="mwAc4" rel="mw:WikiLink" title="Treaty on the Non-Proliferation of Nuclear Weapons">Treaty on the Non-Proliferation of Nuclear Weapons</a> is signed in <a href="https://en.wikipedia.org/wiki/Washington,_D.C." id="mwAc8" rel="mw:WikiLink" title="Washington, D.C.">Washington, D.C.</a>, <a href="https://en.wikipedia.org/wiki/London" id="mwAdA" rel="mw:WikiLink" title="London">London</a> and <a href="https://en.wikipedia.org/wiki/Moscow" id="mwAdE" rel="mw:WikiLink" title="Moscow">Moscow</a> by sixty-two countries.