Attorney-General Christian Porter told federal Parliament on Tuesday afternoon the allegations of the apparent cosy relationship between Crown and government agencies, including favourable visa processing in China, would be probed by the Australian Commission for Law Enforcement Integrity.

Mr Porter said it was important there was "public confidence" in the nation's law enforcement agencies, including immigration and customs, and "all allegations of illegal activity" were taken seriously.

"They hold very privileged positions and, as such, are expected to uphold the highest standards of integrity and professionalism at all times," Mr Porter said.

"I have considered the allegations raised in media reporting... It's my view that there are sufficient concerns to warrant further investigations."

Mr Porter stressed that did not mean he had evidence before him which supported the allegations raised by The Sydney Morning Herald and The Age.

He said it was now a matter for the integrity body to decide whether the allegations warranted further investigation.

Mr Porter said the commission was the most appropriate body to probe the issues, saying it had "significant" investigative powers.

The Coalition and Labor opposed an earlier motion from crossbench MPs to establish a parliamentary inquiry, saying it was "totally ill-equipped" to deal with the allegations and it would be detrimental to run both at the same time.

Independent MP Andrew Wilkie told Parliament the stories published by The Sydney Morning Herald and The Age concerning Crown Resorts were "just the tip of the iceberg".

Mr Wilkie likened the organisation to "the Vatican", saying it appeared to be "an independent sovereign state" where "laws do not apply".

Mr Wilkie said a parliamentary inquiry should look at allegations involving the flagship Melbourne casino, including links to organised crime, money laundering, improper activity by consular officials, tampering with poker machines, and domestic violence and drug trafficking on Crown property.

He told Parliament a whistleblower had told his office "there is no law at Crown... you can do anything you want".