The Treaty, adopted in 2017, will enter into force 90 days after it has been ratified by at least 50 countries and regions.
Kyodo News report so far 49 countries have ratified the pact and one more country is needed.
Although the pact will not be able to legally require nuclear power states to get rid of their arsenals, the launch of the world's first treaty banning nuclear weapons is likely to gain global momentum toward reducing stockpiles.
According to an official of the International Campaign to Abolish Nuclear Weapons, known as ICAN, another country is expected to ratify the treaty in the near future.
But some experts have questioned the potential effectiveness of the nuclear ban treaty, as it would not involve any of the five permanent members of the U.N. Security Council -- Britain, China, France, Russia and the United States, all of which are nuclear power states.
The United States has reportedly pressured some of the signatories as part of its opposition to the pact.
Japan, the only country to have suffered the devastation of atomic bombings when struck shortly before its surrender in World War II, has decided not to sign the treaty in consideration of its security ties with the United States.
Survivors of the atomic bombings on Hiroshima and Nagasaki along with others are calling for the Japanese government to ratify the pact.