A U.N. tribunal set up to prosecute those behind the 2005 assassination of Lebanese Prime Minister Rafik Hariri and related cases said on Wednesday it will have to close after July if it is unable to resolve an acute funding shortage. "The Special Tribunal for Lebanon (STL) regrets to announce that it is facing an unprecedented financial crisis. Without immediate funding, the Tribunal will not be able to operate beyond July 2021," it said in a statement. An exclusive report by Reuters last week revealed the tribunal, which is funded 51% by voluntary contributions and 49% by the Lebanese government, had run out of money. read more Last year the tribunal convicted in absentia former Hezbollah member Salim Jamil Ayyash for the bombing that killed Hariri and 21 others in a ruling that is being appealed. read more . Created by a 2007 U.N. Security Council resolution, the tribunal"s 2020 budget was 55 million euros ($67 million). Wednesday"s statement said that while the 2021 budget was cut by 37% and a $15.5 million contribution had been received from the United Nations on behalf of Lebanon in March, other contributions had not materialised. The closure would leave "important cases unfinished, to the detriment of victims", said Registrar David Tolbert in a statement. Court officials have notified U.N. Secretary General Antonio Gutteres of the situation and judges and other staff are preparing steps to preserve court records and take steps "related to the protection of witnesses", the statement said. The decision would be a blow to families of victims in the Hariri murder and cases in related attacks carried out around the same time that are still under examination. It would also undercut calls for the creation of a new U.N. tribunal to bring to justice those responsible for the Beirut port blast last August that killed 200 and injured 6,500.