Macron says change of Lebanon constitution is not his job

French President Emmanuel Macron on Thursday insisted it was "not his role to recompose Lebanese political life," during a visit to Beirut in the wake of a catastrophic explosion which devastated the city Tuesday.

Macron said he was asked by local leaders and by people in the street to "return to the mandate," when the region was a French protectorate a century ago. He firmly dismissed the idea.

"I am the President of the French Republic," he said, adding "it is up to you to write your history."

Still, he repeatedly referred to close ties between the countries and promised everlasting support for Lebanon after a blast that killed more than 130 people and injured thousands and further ravaged a country already on the verge of economic collapse.

"What I know is that Lebanese people have dozens of power uts every day, (...) increasingly can't fill their stomachs," Macron said. "There are short-term responses to be carried out."

The explosion is believed to have been caused when a fire touched off a stockpile of 2,750 tonnes (3,030 tons) of highly explosive ammonium nitrate that authorities left sitting in a warehouse for years - despite a customs official’s repeated warnings.

On Thursday night, Lebanon's state-run news agency said 16 employees at Beirut's port had been detained over the blast.

Macron said Lebanon should make use of French and other international experts in a UN-supervised investigation.