A Senate inquiry has been warned that relations between Australia and Indonesia could be damaged by the disclosure of documents related to asylum seeker boat interceptions.
Immigration Minister Scott Morrison and Operation Sovereign Borders commander Angus Campbell are giving evidence before an inquiry into government secrecy over border protection operations.
It is the first time a minister from parliament's lower house has fronted a Senate inquiry since 1992.
The Senate's legal and constitutional affairs committee is examining the government's public interest immunity claim to deny the upper house access to official documents.
Lieutenant-General Campbell warned the disclosure of certain documents could undermine international cooperation and agreements.
"The documents requested relate to operational matters that I believe should not be disclosed," he told a hearing of the inquiry in Canberra on Friday.
"These documents may impact upon Australia's relations with foreign states and damage those relationships."
Lieutenant-General Campbell also believed it was too early to provide more information on the 22 boat arrivals that took place in the early phase of the operation, which started on September 18.
Operation Sovereign Borders would not have achieved the objectives it had without a limit on the information it released publicly, he said.
"We would not be where we are today."
There have been no boat arrivals since December 19.