A landmark treaty regulating global arms trade has come into force, www.rferl.org reported.
The first weapons sales agreement outlines global guidelines to regulate the trade, which generates an estimated $85 billion annually.
In a statement, United Nations secretary-general Ban Ki-moon said the treaty "marks the opening of a new chapter in our collective efforts to bring responsibility, accountability, and transparency to the global arms trade."
"Ultimately, it attests to our collective determination to reduce human suffering by preventing the transfer or diversion of weapons to areas afflicted by armed conflict and violence," Ban added.
He further called on all countries to join the agreement "without delay."
According to UN high commissioner for human rights Zeid Ra'ad Al-Hussein, the treaty provided a framework "to end the flow of weaponry that may be used to commit atrocities and other serious human rights violations."
According to campaigners though much work lay ahead in the implementation of the treaty, with a first meeting of states parties to be held in September 2015.
The accord seeks regulation of cross-border transfers of conventional weapons ranging from small firearms to tanks and attack helicopters.
Under the deal, states are required to review contracts to ensure weapons would not be used in human rights abuses, terrorism, violations of humanitarian law, or organised crime.
According to the supporters of the treaty, the development was long overdue, Reuters reported. They say the treaty, which was signed by the US in 2013, would require arms exporters around the world to meet tough export criteria comparable to those in place in the US and other western democracies.
Reuters quoted Anna Macdonald, director of the lobby group Control Arms as saying campaigners have been pushing for this moment for a decade. She added that it would be the "dawn of a new era."
If robustly implemented, this treaty had the potential to save many lives and offer much-needed protection to vulnerable civilians around the world. It was now, finally, against international law to put weapons into the hands of human rights abusers and dictators, she added.
The treaty had been ratified by 60 signatories of the 130 signatories as against the 50 ratifications necessary for the pact to come into force.
The US, the world's top arms exporter, signed the Arms Trade Treaty in September 2013 but it had not be ratified by the US Senate. The opposition had come from the National Rifle Association, a powerful US gun lobby, even though the treaty covered only weapons exports, not domestic gun sales.