A senior Metropolitan Police officer has said he “cannot imagine” how it feels for families and victims to wait for the outcome of a police investigation into the Grenfell Tower fire.

Those affected by the disaster face a wait of another year to 18 months from the report’s publication before they find out whether any criminal charges will be brought over the tragedy.

Police and prosecutors said in May that investigators will need until the end of 2025 to complete their inquiry, with final decisions on potential criminal charges by the end of 2026.

Speaking outside Scotland Yard on Wednesday, Metropolitan Police Deputy Assistant Commissioner Stuart Cundy said he “cannot imagine” the impact of such a long wait.

“I cannot imagine the impact of such a long criminal investigation and public inquiry, and what that impact is on those that are so deeply affected,” he said.

“But I’ve spoken to many of them at different times over the last seven years, they have my personal commitment, the commitment of the Met Police, that we will do everything that we can to secure justice for those who died.”

He said the criminal investigation could not use the inquiry’s final report as evidence due to “different legal arrangements”.

“We have followed all the evidence, but because of the different legal arrangements, the criminal investigation cannot simply use the inquiry’s final report as evidence,” he said.

“But it is a very, very significant document, on such a significant day following the Grenfell tragedy.”

He said police only have “one chance” to get the investigation right.

“Those affected absolutely have my commitment that we will be presenting a case to the Crown prosecutor’s service,” he said.

“We will do it as soon as we can, but we have one chance to get this right.”

In May, the Met said its mammoth inquiry into the fire, which killed 72 people in 2017, had generated 27,000 lines of inquiry and more than 12,000 witness statements.

A total of 19 companies and organisations were under investigation for potential criminal offences, along with 58 individuals, and more than 300 hours of interviews had taken place.

Mr Cundy said the investigation was one of the most complex ever undertaken by the force.

He added: “Our investigation started on June 14, 2017.

“We still have 180 investigators permanently working on this investigation, which is one of the most large and complex investigations the Met Police has ever undertaken, to secure justice for those who died and everybody’s been affected by tragedy.”

Potential offences under consideration included corporate manslaughter, gross negligence manslaughter, perverting the course of justice, misconduct in public office, health and safety offences, fraud, and offences under the fire safety and building regulations.

At that stage, eight out of 20 files had been sent to the CPS for early investigative advice, with a typical case file more than 500 pages long with 17,000 pages of evidence.

Up to the end of March this year, the Met had spent £107.3 million on the inquiry.

Officers had retrieved more than 152 million files, gathered 75,000 photos and 27,000 exhibits.

Forensic teams spent 415 days examining the tower itself after the deadly blaze and painstakingly gathering evidence.

Exhibits are being stored in an enormous warehouse that is big enough to store 25 double-decker buses.

It includes the charred remnants of cladding panels that would have had molten plastic dripping down them while the building was on fire.