The new boss of Britain’s biggest police force has described preparations for the Queen’s lying in state as a “massive challenge” during his first day in the job.

Sir Mark Rowley said the operation, which will involve thousands of officers, was something “we have been preparing for many, many years” as he started work as Commissioner of the Metropolitan Police on Monday.

He told Sky News: “It’s a massive challenge for the Metropolitan Police and for me personally, but we have been preparing for many, many years.

“There are some very diligent and determined people who have put a lot of effort into this, and indeed myself in my previous roles in the Metropolitan Police – five or six years ago I was involved in some of that planning and I have been involved in a review recently.

“But most of all I have a lot of trust and confidence in the fantastic police officers who are going to support this event and help make it safe.

“They have been working with colleagues from across Government and the Royal Household and others, as you would expect.

“We will have a safe event but we will be putting thousands of officers into this because of the level of security required and the millions of people who want to pay their respects.”

Sir Mark has taken over as head of Scotland Yard during what is arguably one of its most turbulent times. He was appointed to the role after former boss Dame Cressida Dick dramatically quit earlier this year.

He, along with his new deputy Dame Lynne Owens who used to be the director of the National Crime Agency, swore allegiance to the King on Monday morning and pledged to rebuild public trust.