Hassan Diab
Mustapha Adib was named before French President Emmanuel Macron arrived in Beirut to push for reforms as the country faces several threats to its stability.
The explosion has fueled popular outrage against the country's top political leaders and security agencies, and led to the resignation of the government on Monday.
Anti-government protests erupted in Beirut after a warehouse explosion killed at least 160 people and injured thousands.
Protests against the country's ruling elite have erupted in Beirut following the massive blast in a Beirut Port warehouse.
WHAT'S HAPPENING
The country's unparalleled economic and financial crises are proving a major challenge to the government of Prime Minister Hassan Diab.
Earlier in the day, Lebanese security forces fired tear gas to disperse thousands of demonstrators near the parliament building in Beirut.