The massive explosion and devastation triggered by thousands of tons of chemicals improperly stored in Beirut's port is the culmination of decades of corruption that has driven one of the Middle East's most spirited countries to ruin.

The staggering destruction, with losses in the billions of dollars, will compound Lebanon's multiple humanitarian catastrophes. Its people are seething with rage as they are pushed into even more poverty and despair by an accident that appears to have been completely avoidable.

Lebanese security forces late Thursday fired tear gas to disperse dozens of anti-government demonstrators angered by a cataclysmic blast widely seen as the most shocking expression yet of their government's incompetence.

Progressive Socialist Party leader Walid Jumblat on Thursday called for tasking an international panel of inquiry with probing the mega-blast that rocked Beirut’s port, as he stressed that the Democratic Gathering bloc will not resign from parliament.

French President Emmanuel Macron held a meeting Thursday at the Baabda Palace with President Michel Aoun, Speaker Nabih Berri and Prime Minister Hassan Diab.

The colossal explosion that devastated Beirut's port and gutted entire neighbourhoods of the Lebanese capital deals a fresh blow to an already fragile and deeply unpopular government.

Defence Secretary Ben Wallace has authorised the deployment of HMS Enterprise in support of the Lebanese government at this tragic time, the British embassy announced in a statement on Thursday.

The Armed Forces will continue to work with the Lebanese government to help the people of Beirut recover. A small team of experts will deploy to the British Embassy in Beirut to help coordinate the UK response ahead of HMS Enterprise's deployment and a further package of support.

The huge blast at Beirut port has killed at least 137 people, left dozens missing and at least 5,000 wounded, a Lebanese health ministry spokesperson said Thursday.

The U.N.-backed Special Tribunal for Lebanon on Wednesday announced the postponement of its verdict in the Rafik Hariri case to August 18, saying the move comes "out of respect for the countless victims" of Tuesday's Beirut blast.

"The Special Tribunal for Lebanon (STL) is deeply saddened and shocked by the tragic events that shook Lebanon yesterday. The Tribunal expresses its solidarity with the Lebanese people in these difficult times," it said in a statement.

Qatar began flying field hospitals and medical aid to Beirut Wednesday, AFP correspondents saw, to ease pressure on Lebanon's strained medical system after the previous day's devastating explosions.