The State of Palestine asserted in an application (PDF) submitted to the International Court of Justice (ICJ) on Sept. 28 that the recent relocation of the US embassy from Tel Aviv to Jerusalem constitutes a breach of international diplomatic law. In support of its claim, Palestine directed the ICJ to multiple UN General Assembly and Security Council resolutions affirming the special international regime that applies to Jerusalem and calling on member states to refrain from recognizing Jerusalem as Israeli territory. Palestine argued that establishment of an embassy to Israel in Jerusalem violates provisions of the Vienna Convention on Diplomatic Relations (PDF) governing activities in the "receiving state."

Yemen war crime investigators on Sept. 25 called upon the UN Human Rights Council to renew their mandate and allow the continued inquiry into Yemen's internal conflict, calling the situation in the county "extremely alarming." The Group of Eminent Experts on Yemen, in their initial report (PDF), released in August, found evidence that "members of the Saudi-led coalition, the Yemeni government, and the Houthi armed group have been committing abuses, including indiscriminate and disproportionate attacks on civilians, arbitrary and abusive detention, and recruitment of children." At the time of the report, the experts recommended that their mandate be renewed. However, Saudi Arabia and other coalition members have pressed the council to discontinue the inquiry.

UN investigators on Sept. 18 renewed their call for charges against Burma military officials suspected of carrying out a genocide against the nation's minority Rohingya population over the past year. The UN Office of Human Rights published an exhaustive list of atrocities and called "for the investigation and prosecution of Myanmar's Commander-in-Chief, Senior General Min Aung Hlaing, and his top military leaders for genocide, crimes against humanity and war crimes." Since last August, 700,000 Rohinga refugees have fled into neighboring Bangladesh, and many have spoken of the Burmese military's attacks on their villages, describing actions that are considered crimes against humanity under international law. This August, a UN fact-fidning mission for the first time referred to the ethnic conflict in Burma as a genocide. Burma's government officially rejected the charges.

Six UN Special Rapporteurs called on the UN Human Rights Council (UNHRC) on Sept. 17 to respond to a recent Egyptian court decision that condemned 75 protesters to death. The court sentenced another 47 protesters to life in prison. The protesters were charged with illegal gathering, involvement in violence, and incitement to break the law. The Special Rapporteurs state that those who have been sentenced did not receive a fair trial, as they were not given the right to present evidence in their defense. The UNHRC was called upon to "send a strong message to all States that they have a duty under international law to investigate arbitrary killings and prosecute those responsible as well as to apply due process and fair trial standards." The Special Rapporteurs said the executions would be "arbitrary deprivations of life,” and stated that the life prison sentences are “grossly disproportionate and, therefore, may well amount to cruel, inhuman or degrading punishment."

Amnesty International called upon countries to ban fully autonomous weapons systems on Aug. 27, the first day of the UN Convention on Certain Conventional Weapons (CCW) Group of Governmental Experts on Lethal Autonomous Weapons Systems meeting in Geneva. Amnesty states that technology related to advanced weapons systems is outpacing international law. Future technologies may be able to replicate human responses, including "the ability to analyse the intentions behind people's actions, to assess and respond to often dynamic and unpredictable situations, or make complex decisions about the proportionality or necessity of an attack." A complete ban on fully autonomous weapons is necessary in order to avoid possible "dystopian" futures. Human interaction should be required by law to be involved in the identification, selection, and engagement of targets in advanced weapons.

The 18 member states of the Pacific Islands Forum held their 49th summit in Nauru, issuing a statement (PDFi) Sept. 6 asserting that "climate change presents the single greatest threat to the livelihood, security and wellbeing of Pacific people." The leaders "reaffirmed the importance of immediate urgent action to combat climate change" and committed "to ensure effective progress on Pacific priorities with regards to the Paris Agreement" through the development of a guide. Leaders at the Forum also urged all countries to comply fully with their commitments to mitigate emissions, "including through the development and transfer of renewable energy," within their committed timeframes. The leaders also "called on the United States to return to the Paris Agreement on Climate Change."

The White House announced Sept. 10 that the US will consider imposing sanctions against the International Criminal Court (ICC) judges and prosecutors if the ICC opens an investigation into the actions of United States service members and intelligence personnel in Afghanistan. The Chief Prosecutor of the ICC requested an investigation in November 2017 into alleged war crimes committed by the US in Afghanistan since May 2003, in addition to actions taken by the Afghan National Security Forces, the Taliban and the Haqqani network. In addition to sanctions, the US will consider seeking to have the ICC's powers restricted by the UN Security Council. The US will also seek to strengthen agreements that would prevent other nations from surrendering US nationals to the ICC.

The government of the island nation of Mauritius presented its claim Sept. 3 to the International Court of Justice (ICJ) that the British government forced the transfer of the Chagos Islands as a condition of independence in 1965. The UK leased the island of Diego Garcia within the Chagos archipelago to the US in 1966, which was used to build a military base that required the forced removal of around 1,500 people. The population has yet to be allowed to return home. The former prime minister of Mauritius and current parliamentarian Anerood Jugnauth told the ICJ, “The choice we were faced with was no choice at all: it was independence with detachment [of the Chagos archipelago] or no independence with detachment anyway.” The location of the Chagos Islands in the central Indian Ocean is seen as geopolitically strategic for policing the Persian Gulf. In 2016 the US lease for the base was extended until 2036.