Emergency services carried out a training exercise at the Israeli embassy in London to practise the response to an attack using hazardous substances.

Sunday’s operation, near to Kensington Palace, was not prompted by any specific threat and was unrelated to US President Donald Trump’s decision to officially recognise Jerusalem as Israel’s capital city.

The JC understands it had been planned roughly a year in advance.

About 50 members of the Royal Military Police Reserves posed as casualties and embassy staff, while firefighters, paramedics and police officers donned bio-suits to take part in the exercise.

Actual embassy staff members were not involved in the “live play” exercise.

It was the first live-play exercise involving police and other emergency services to take place at a foreign embassy in London.

Metropolitan Police Commander Adrian Usher, who leads the force’s parliamentary and diplomatic protection command, said: "(The exercise) tested our joint response in dealing with a hazardous substance, which is important as it will help officers and staff be better prepared should we ever face this type of challenge for real.

"I must stress, however, that the exercise, which has been planned over several months, was not designed with any specific threat in mind either in terms of the hazardous material element or the location."

A spokesperson from the embassy said they were happy to participate and work with the emergency services.