Vanuatu's Foreign Minister Ralph Regenvanu said last year his government was considering legal action against fossil fuel corporations and countries.
In September, Vanuatu invited legal experts from around the world to discuss possible avenues for the lawsuit.
Columbia Law School professor Michael Gerrard said the government wanted an advisory opinion from the World Court.
"There are courts in several different countries that are now adjudicating the obligation of emittors in their own countries to reduce their greenhouse gas emissions. A decision from the International Court of Justice could be quite powerful in influencing those domestic courts," Professor Gerrard said.
Vanuatu's plan could be stymied, however, because it needs majority support in the UN General Assembly, he said.
"[The] problem is that here several countries would actively oppose it and that poses some obstacles. In 2013, the Republic of the Marshall Islands and Tuvalu wanted to get in front of the ICJ but the US actively opposed it."