Mr Johnson said the Government is “ready to provide support in any way we can”. He added Foreign Secretary Dominic Raab said the UK stands in solidarity with Lebanon. It comes ater videos of a huge mushroom cloud rising above the Middle Eastern city were shared on social media.
At least 50 people were killed and 2,700 injured, with bodies buried in the rubble, officials said.
Authorities in Lebanon are yet to announce the cause of the explosion.
In a tweet, Mr Johnson said: “The pictures and videos from Beirut tonight are shocking.
“All of my thoughts and prayers are with those caught up in this terrible incident.
“The UK is ready to provide support in any way we can, including to those British nationals affected.”
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