Preliminary hearings began Monday at the United Nation's highest court in a case aiming to halt German military and other aid to Israel.
The case alleges that Berlin is complicit in acts of genocide and violations of international humanitarian law in the Israel-Hamas conflict in Gaza.
Nicaragua argues that by providing political, financial and military support to Israel and defunding the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), "Germany is facilitating genocide and has failed in its obligation to prevent it."
During Nicaragua's presentation at the International Court of Justice, Nicaraguan Ambassador to the Netherlands Carlos Jose Arguello Gomez stated that "Germany is not honoring its obligation to prevent genocide or uphold international humanitarian law."
While Nicaragua's case focuses on Germany, it indirectly criticizes Israel's military actions in Gaza following the Oct. 7 Hamas incursion on southern Israel.
Gaza's Health Ministry reports over 33,000 Palestinian deaths, with the majority being women and children.
Israel strongly denies that its assault amounts to genocidal acts, saying it is acting in self-defense. Israeli legal adviser Tal Becker told judges at the court earlier this year that the country is fighting a "war it did not start and did not want."
Germany rejects the case brought by Nicaragua.
"Germany has breached neither the Genocide Convention nor international humanitarian law and we will set this out in detail before the International Court of Justice," German Foreign Ministry spokesperson Sebastian Fischer told reporters in Berlin on Friday.
Nicaragua has asked the court to hand down preliminary orders known as provisional measures, including that Germany "immediately suspend its aid to Israel, in particular its military assistance, including military equipment, in so far as this aid may be used in the violation of the Genocide Convention" and international law.
The court will likely take weeks to deliver its preliminary decision and Nicaragua's case will probably drag on for years.
Monday's hearing at the world court comes amid growing calls for allies to stop supplying arms to Israel as its six-month campaign continues to lay waste to Gaza.
The offensive has displaced the vast majority of Gaza's population. Food is scarce, the U.N. says famine is approaching and few Palestinians have been able to leave the besieged territory.
The case "will likely further galvanize opposition to any support for Israel," said Mary Ellen O'Connell, a professor of law and international peace studies at the University of Notre Dame.
On Friday, the U.N.'s top human rights body called on countries to stop selling or shipping weapons to Israel. The United States and Germany opposed the resolution.
Also, hundreds of British jurists, including three retired Supreme Court judges, have called on their government to suspend arms sales to Israel after three U.K. citizens were among seven aid workers from the charity World Central Kitchen killed in Israeli strikes. Israel said the attack on the aid workers was a mistake caused by "misidentification."
Germany has for decades been a staunch supporter of Israel.
Days after Oct. 7, Chancellor Olaf Scholz explained why: "Our own history, our responsibility arising from the Holocaust, makes it a perpetual task for us to stand up for the security of the state of Israel."
Berlin, however, has gradually shifted its tone as civilian casualties in Gaza have soared, becoming increasingly critical of the humanitarian situation in Gaza and speaking out against a ground offensive in Rafah.
Nicaragua's government, which has historical links with Palestinian organizations dating back to their support for the 1979 Sandinista revolution, was itself accused earlier this year by U.N.-backed human rights experts of systematic human rights abuses "tantamount to crimes against humanity." The government of President Daniel Ortega fiercely rejected the allegations.
In January, the ICJ imposed provisional measures ordering Israel to do all it can to prevent death, destruction and acts of genocide in Gaza. The orders came in a case filed by South Africa accusing Israel of breaching the Genocide Convention.
The court last week ordered Israel to take measures to improve the humanitarian situation in Gaza, including opening more land crossings to allow food, water, fuel and other supplies into the war-ravaged enclave.