A U.N. human rights expert says he has postponed his visit to Australia because the government has refused to suspend a law criminalizing the disclosure of "protected information" about detention centers.

The U.N. special investigator on migration, Francois Crepeau, said in a statement late Friday that he asked the Australian government to guarantee that nobody would face sanctions or intimidation for talking to him.

Crepeau says that "as the Australian government was not prepared to give the written assurances ... it was not possible for me to carry out the visit in my capacity as a U.N. independent expert."

He had planned to visit Australia and off-shore detention centers in neighboring Nauru and Papua New Guinea during a trip from Sept. 27 to Oct. 9.