A UN-backed tribunal into the assassination of former Lebanese prime minister Rafiq Hariri in a huge suicide bombing 2005 will deliver its long-awaited verdict on August 7, the court announced on Friday. Four suspects from the Shiite Muslim fundamentalist group Hezbollah are on trial over the murder of billionaire Hariri, who was killed on Valentine's Day when the bomber detonated a van next to his armoured convoy on the Beirut seafront. Another 21 people were killed and 226 injured in the assassination of Hariri, who was Lebanon's Sunni premier until his resignation in 2004 over Syria's role as a power-broker in the country. The Netherlands-based court said it "issued a scheduling order today for the public pronouncement of the judgment" in the case against the suspects, who are being tried in absentia after Hezbollah chief Hassan Nasrallah refused to hand them over. Due to the coronavirus pandemic, the hearing "will be delivered from the courtroom with partial virtual participation", it said in statement. Salim Ayyash is accused of leading the team that carried out the bombing, while Assad Sabra, and Hussein Oneissi, allegedly sent a fake video to the Al-Jazeera news channel claiming responsibility on behalf of a made-up group. Hassan Habib Merhi, is accused of general involvement in the plot. The alleged mastermind of the bombing, Hezbollah commander Mustafa Badreddine, was indicted by the court but is believed to have died while leading the militia's forces fighting with the Syrian regime in May 2016. The assassination of Hariri transformed the face of the Middle East, triggering a wave of mass demonstrations that ended with the departure of Syrian forces from Lebanon after a 30-year presence. - 'Severe threat' - However the trial remains a sensitive subject in Lebanon, which is politically unstable and crippled with its worst economic crisis since the 1975-1990 civil war. The tribunal was created by a 2007 UN Security Council resolution at Lebanon's request, and the four defendants went on trial in 2014 accused of core roles in the deadly attack. Prosecutors said during the trial that Hariri was assassinated because he was perceived as a "severe threat" to Syrian control of the country and as a "proxy of the West". They said their case was "circumstantial" but "compelling", relying almost entirely on mobile phone records allegedly showing the suspects conducting intense surveillance of Hariri from just after his resignation until minutes before the blast. But the absence of the defendants has raised questions about the trial's credibility, while the gap of 13 years since the attack has caused doubts about its relevance in a region transformed by the war in Syria. Hezbollah's Hassan Nasrallah has refused to hand over the suspects and warned the tribunal "don't play with fire" while Syrian leader Bashar al-Assad says it is a tool to "pressure Hezbollah". Rafiq Hariri's son Saad, who later went on to become prime minister like his father, called at the conclusion of the hearings in 2018 for "justice" but not revenge. The court has heard evidence from more than 300 witnesses and amassed 144,000 pages of evidence - at an estimated cost of at least $600 million since it opened its doors in 2009. The tribunal opened a second case last year, charging prime suspect Ayyash with terrorism and murder over deadly attacks on politicians in 2004 and 2005.