In the briefing, it is expected he will see at least five current or former New Zealand internationals have offered statements to investigators, including testimony from Brendon McCullum and Lou Vincent that has already been widely distributed.
The full disclosure could be an indication Scotland Yard is close to a decision on whether to lay charges although Cairns is understood to have a written guarantee that he will not be detained and is free to return to New Zealand this week.
Cairns has consistently denied any wrongdoing.
The Herald requested comment from Cairns' attorney, Aaron Lloyd -- who has represented New Zealand Cricket previously -- but he has not returned calls or emails. However, an automatic reply on his email address suggests he will be back at work in New Zealand on Friday.
On Monday night Cairns sent a series of tweets saying he was respecting the confidentiality of the Met Police process and would comment when he could.
Legal experts spoken to last night under the condition of anonymity said they believed the Met Police would present their evidence to the Crown Prosecution Service, who would determine what, if any, charges will be laid.
A spokesman for the Met Police yesterday said that although Cairns had waived his right to anonymity by confirming he was travelling to London for the interview, they would not be changing their policy of not discussing an ongoing investigation.
With Cairns concluding interviews with the Met Police, it now opens the way for the ICC anti-corruption unit (ACSU) to begin questioning the former New Zealand allrounder.
Chairman of the ACSU, Sir Ronnie Flanagan, yesterday told the Herald: "A criminal investigation will always take primacy. We make sure anything we do does not interfere with a criminal investigation.
"There are times we would wish to conduct interviews but would hold back at the request of their [officers]."
Cairns has expressed frustration at the time it has taken for ACSU officers to contact him.
The Herald broke the news in December that three former internationals -- Cairns, Lou Vincent and Daryl Tuffey -- were under ICC investigation.
Vincent has said he is fully co-operating with the investigation. He has been charged by the England and Wales Cricket Board for fixing in limited overs county matches and is expecting more charges to be laid in relation to match-fixing at the Champions League, when he was playing for the Auckland Aces. Cairns and Tuffey have repeatedly denied any involvement in match-fixing.
- Dylan Cleaver of the New Zealand Herald and Andrew Alderson of the Herald on Sunday
