Border Force boss had 'inappropriate relationship with young female staffer'

The head of Australian Border Force has taken "personal leave" amid allegations he was involved in an inappropriate relationship with a young female staffer.

Senior government officials have refused to comment on an investigation involving Commissioner Roman Quaedvlieg since he took leave earlier this year.

Allegations that the married 52-year-old breached protocol by getting involved in an inappropriate relationship with a female staffer in her 20s emerged on Tuesday, the Daily Telegraph reported.

The staffer in question reportedly received a promotion.

Quaedvlieg, who earns $731,000 from his high-profile government job, has not been seen in Parliament House since late May.

Acting Immigration Minister Michael Keenan said the matter is currently "under consideration by appropriate authorities on Monday night.

"There will be no further comment until that process is complete," he said.

Quaedvlieg has not commented.