The massive explosion at Beirut's port on Tuesday is threatening to plunge even more Lebanese into hunger, Christian Aid has warned. 

The development agency said the blast had destroyed livelihoods at a time when the country - home to a million Syrian refugees - was already on the brink after months of social and economic crisis. 

"The horrific and shocking explosion in Beirut comes amid what was already a perfect storm in Lebanon of displacement, pandemic, civil unrest, government corruption and economic crisis," it said. 

"This morning our partners are waking up to devastation in Lebanon's capital city. There are scarcely any homes that are not damaged, with many destroyed; businesses and livelihoods were wiped out in seconds." 

The IMF predicts Lebanon's GDP will shrink by 12%, the worst in 30 years, with poverty expected to rise among the Lebanese by 52%, and among Syrian refugees by 83%.

Covid-19 has only worsened the crisis, with many workers experiencing a "steep drop" in living standards during the pandemic. 

"These people have no social protection to help them weather the economic crisis," Christian Aid said. 

Its partner in Lebanon, Basmeh & Zeitooneh, was already reporting widespread hunger in April, with some families having no food at all at home. 

Now, after the explosion, the food crisis will "deepen further", Christian Aid said. 

"The grain stores in the port are completely destroyed. The port is the entry way for Lebanon's grain imports; they import 90% of their grain for the staple Lebanese bread," it said.

"This explosion has made a very dire situation worse – with a growing number of Lebanese vulnerable to destitution - and could not have come at a worse time for the besieged country."