A Courtauld Gallery security guard, who gave his name as Rafal K, said the firefighters’ work appears to be finished.

He exited the cordon shortly before 3pm and told the PA news agency: “It’s still not clear to let people back in, but it looks like the action of the firemen is finished.

“I’m still waiting for the manager on the shift to bring people back in.

“It will be security (who go in) first and then members of the public who can get their belongings in their lockers.”

He said he believes the locker room was “untouched” by the fire.

The plumes of smoke that were still visible inside the courtyard shortly before 2pm appeared to have disappeared.

Firefighters were sitting in chairs overlooking Somerset House, wearing t-shirts with their kit at their feet.