A U.N.-backed tribunal said on Wednesday it had suspended a verdict on the 2005 murder of former Lebanese premier Rafik Hariri following the deadly blast in Beirut.

The court's decision was due on Friday but the ruling has been postponed until Aug. 18, the court said in a statement.

Four alleged members of Hezbollah are on trial in absentia at the court in the Netherlands over the huge Beirut suicide bombing that killed Sunni billionaire Hariri and 21 other people.

The judgment harks back to an event that changed the face of the Middle East, with Hariri’s assassination triggering a wave of demonstrations that pushed Syrian forces out of Lebanon after 30 years. Hariri was Lebanon’s Sunni premier until his resignation in 2004 over Syria’s role as a power-broker in the country. Prosecutors said during the trial that Hariri was assassinated because he was perceived to be a "severe threat" to Syrian control of the country.

The court is billed as the world’s first international tribunal set up to probe terrorist crimes, and it has cost at least $600 million since it opened its doors in 2009 following a U.N. Security Council (UNSC) resolution. But the tribunal faces doubts over its credibility with Hezbollah chief Hassan Nasrallah refusing to hand over the defendants and the case relying almost entirely on mobile phone records.