Willis is the broker for London jewellers raided by gunmen in UK's second biggest robbery

XL is the lead insurer for Graff, the London jewellers raided by two gunmen in a £40m heist, Insurance Times understands.

This latest development comes after market sources earlier told Insurance Times that Willis was the broker in what Met Police said was the second biggest robbery in Britain, only exceeded by the £53m raid on a Securitas depot in Kent in 2006.

The robbery at New Bond Street, in which 43 high net worth items wore taken, happened on 6 August but details were only revealed by police yesterday.

Female staff members were dragged outside by the two smartly-dressed men, who fired a shot, although no-one was injured. They escaped in a blue BMW.

Detective Chief Inspector Pam Mace from the Flying Squad said: "This was a well planned robbery with a number of vehicles used to help the robbers escape.

"These men are extremely dangerous and fired at least two shots in busy London streets as they made their getaway.

"Someone knows who these men are, they would undoubtedly have spoken about it beforehand or boasted about it afterwards."

Insurance Times understands Willis won the contract for Graff in 2007 and was the broker last year. The situation is not thought to have changed.

Willis and XL declined to comment.

For more, see next week’s Insurance Times.