The UN court is to decide whether to take up a case brought by the Marshall Islands against India, Pakistan and Britain for allegedly failing to halt the nuclear arms race.
The decision by the 16-judge bench at the International Court of Justice will determine whether the battle can continue to a full hearing.
In this regard Majuro seeks to shine a fresh spotlight on the threat of nuclear weapons. The tiny Pacific island nation was ground zero for a string of nuclear tests on its pristine atolls in between 1946-58.
The tests were carried out by the United States as the Cold War arms race gathered momentum. The country of 55,000 people is willing to testify with authority about the devastating impact of such arms.
Initially in 2014, Majuro accused nine countries of failing to comply with the 1968 nuclear Non-Proliferation Treaty, which seeks to inhibit the spread of atomic bombs.
The ICJ set up in The Hague in 1945 to rule on disputes between states will only determine whether it is competent to hear three cases -- against Britain, India and Pakistan.
The other countries -- China, France, Israel, North Korea, Russia and the United States have not recognized the court's jurisdiction. Israel has also never formally admitted to having nuclear weapons.
Marshall Islands quoted that by not stopping the nuclear arms race Britain, India and Pakistan continued to breach obligations under the treaty even if New Delhi and Islamabad have not signed the pact.
The treaty commits all nuclear weapon states to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament.