The State Services Commission will be forced into an embarrassing climb-down over an inquiry into leaks from the Foreign Affairs ministry.

ONE News has learned two former diplomats are in line for a public apology and compensation after they were named in a 2013 report by Paula Rebstock.

An investigation from Ombudsman Ron Paterson, due later this week, is expected to heavily criticise the report's author and the State Services Commission, which commissioned it.

This all goes back to 2012 when Labour's Phil Goff was leaked cabinet documents on plans to make sweeping job cuts at MFAT.

Ms Rebstock - known as the Government's enforcer - was brought in to investigate.

Her $500,000 report couldn't identify the leaker but said the likely culprit was a former Labour staffer. But it also accused two senior diplomats - Derek Leask and Nigel Fyfe - of "disrupting" the restructuring plan by encouraging opposition.

Foreign Minister Murray McCully also attacked the two diplomats calling them "unprofessional and disreputable".

Initially, they weren't named - but their names leaked out.

Mr Leask – a former MFAT deputy secretary and High Commissioner to London hit back - taking his case to the Ombudsman and engaging a lawyer. He argued the report was flawed and the State Services Commissioner Iain Rennie should never have allowed it to be published. He also demanded a public apology.

Now, after months of legal wrangling the SSC looks set to deliver that apology.

Rennie is understood to have already apologised privately to Mr Leask in a letter.

The two men are also in line for a pay-out – to cover legal bills from the last four years. It's understood Mr Leask is also in line for damages.

Rebstock recently chaired a major review of Child, Youth and Family, controversially earning $2000 a day for the work.