The Treaty on the Prohibition of Nuclear Weapons negotiations took place over four weeks in 2017, from 27 to 31 March and from 15 June to 7 July 2017. Much of these negotiations built upon the work and discussions of the three sessions of the open-ended working group in 2016 established by the First Committee of the United Nations (UN) General Assembly in 2015. The nuclear umbrella States tried to counter the strengthening momentum towards a ban treaty. Under Australian coordination, Broadly Likeminded Group of States presented a working paper that outlined a so-called “progressive approach” as an alternative to the ban treaty. It argued that a prohibition of nuclear weapons would be possible only as the final building block, once all the other “effective practical measures” have been implemented. During the August 2016 session of the open-ended working group, intensive negotiations took place regarding the final report to the UN General Assembly, the aim being adoption without a vote.