Deputy assistant commissioner Kevin Southworth said a team of 220 investigators had worked hard on the case but he appreciates “it has taken nine years to get to this point”.
“As we have said before, this is one of the most complex investigations ever undertaken by any UK law enforcement agency – the scale is truly enormous.
“While we know this has had a significant impact on those waiting for answers, it has necessarily taken this long to ensure our investigation is meticulous and presents the very best possible evidence to the CPS for charging decisions,” he added.
The CPS will decide whether there is a realistic prospect of conviction, as well as considering whether bringing charges is in the public interest.
In anticipation of possible criminal proceedings, the Met has said it is building a £2m replica of a section of the tower, which is being dismantled, to help future jurors understand its layout.
Frank Ferguson, head of the CPS special crime and counter terrorism division, said it marked “an important step”.
“We recognise that the journey to this point has been long and difficult.
“Charging decisions will be made independently by CPS prosecutors following a thorough and careful review of all the evidence gathered by the Metropolitan Police Service,” he added.
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