A number of MPs have joined Rt Rev Stephen Cottrell, the Anglican Bishop of Chelmsford and Most Rev Malcolm McMahon, the Catholic Archbishop of Liverpool in urging the Prime Minister to put the UK's signature on the treaty and pledge to abolish nuclear weapons.
Juliet Prager, from Quakers in Britain, also signed the letter. Speaking on Premier's News Hour, she said: "We really believe in the Christian value of hope, we think that's very profound and is completely in opposition to death and destruction which is symbolised by nuclear weapons."
Over 100 states are expected to sign the treaty in the coming days, with the US and UK choosing not to.
Calling for a rethink, Prager said: "Putting our money, our intelligent brains and energy into arming the world is something about fear.
"It's a really frightened approach to the world and they are so many better things our resources can be used for."