Churches and church alliance have lobbied and eight more governments are ratifying the Arms Trade Treaty (ATT) during last week's high-level meetings at the United Nations.
The latest actions mean that 53 governments, including several lobbied by the member churches of the World Council of Churches have ratified the new treaty, the WCC said in a statement.
The treaty will now come into effect by the end of 2014.
Armed conflict in the Middle East has preoccupied world leaders gathered in New York.
"To watch the news is to be reminded daily of how sorely a strong and effective ATT is needed," the WCC general secretary Rev. Olav Fykse Tveit said.
"Human life and human dignity, God's great gifts to each of us, are being battered by armed violence in many places. Controlling the arms trade is a requirement for stopping the terror and violence in the world today," he said.
Church advocates led by the WCC have lobbied for a strong and effective ATT with up to 50 governments for the past four years, often in collaboration with civil society partners.
Almost all of those governments have now signed the treaty and seven have ratified it, most recently Sierra Leone.
Another country, Namibia, is set to sign and ratify the ATT on 25 September. The ecumenical ATT campaign has a focus on Africa, given the number of countries and communities suffering the consequences of the illicit arms trade in the region.
"The ATT with its human-centered provisions is long overdue," said Tveit. "These first 50 ratifications must move us closer to a treaty that no state and no arms dealer can ignore."
By signing the ATT, States commit themselves to regulate all transfers of conventional arms and components; ban exports of arms when there is a substantial risk of war crimes, genocide or attacks against civilians; assess risks related to human rights violations, terrorism, organized crime or gender-based violence; and avoid arms shipments being diverted from the authorized user.
Recent research in Iraq and Syria shows that weapons made in the United States and China are being used by the militant group Islamic State in Iraq and Syria, says a report by Conflict Armament Research.
The Control Arms Coalition points out the increasing scrutiny of who is supplying the weapons fuelling the current spate of armed conflicts. The ATT is entering into force in record time compared to other multilateral arms treaties.