UNITED NATIONS — The International Criminal Court’s chief prosecutor said Wednesday the war crimes tribunal would allow the Palestinians to sign up if the U.N. General Assembly approves a resolution recognizing Palestine as a non-member observer state.

Prosecutor Luis Moreno-Ocampo ruled Tuesday that only internationally recognized states can join the court, and therefore the Palestinian Authority’s bid for membership could not be accepted.

The Palestinian Authority unilaterally recognized the court’s jurisdiction in January 2009, hoping to clear the way for the tribunal to investigate an Israeli military offensive in the Gaza Strip that began in December 2008. Recognition would be the first step in a process that could have finished with Israel being investigated for possible war crimes.

Moreno-Ocampo said in an interview with The Associated Press that becoming a U.N. nonmember observer state would be the easiest path for Palestine to become a party to the Rome Statute which established the court. Palestine is a permanent observer at the U.N., which is one step behind a nonmember observer state.

“Basically the issue for me is, I have no authority to define who’s a state,” he said. “In the case of Palestine, the question is, is Palestine a state in accordance with the Rome statute or not.”

The statute has a process, and the first step is for the U.N. secretary-general to confirm that an applicant is a state, Moreno-Ocampo said. If the secretary-general has doubts, or if there is controversy, the practice is to request the guidance of the General Assembly and the secretary-general will follow the guidance of the 193-member world body, he said.

“That’s why, as soon as the General Assembly establishes that Palestine is an observer state, then we can proceed,” Moreno-Ocampo said.

The Palestinians made a bid for full U.N. membership last fall but it remains stalled.

For Palestine to become a U.N. member state, it needs the recommendation of the 15-member Security Council. That requires nine “yes” votes — which the Palestinians don’t appear to have — and no veto by a permanent member.

The United States, Israel’s closest ally, insists on a negotiated settlement of the Israeli-Palestinian conflict before Palestine joins the U.N. and says it will veto a resolution recommending its membership now, if necessary.

Riad Malki, the Palestinian foreign minister, said its options include reviving the bid for full membership or seeking General Assembly recognition of Palestine as a nonmember observer state. He emphasized that nothing has been decided.