London-based human rights lawyer Jennifer Robinson said on Thursday airport authorities in London had informed her she was on an "inhibited travel list".
"Just delayed from checking in at (London Heathrow Airport) because I'm apparently "inhibited" - requiring approval from Australia House @dfat to travel," she tweeted.
Security guards told her "you must have done something controversial because we have to phone the embassy," Ms Robinson said.
She asked the Australian authorities for an explanation.
"@dfat Please explain: What is the "inhibited" travel list? And why am I now apparently on it?" she tweeted.
Ms Robinson may get the opportunity to ask Attorney-General Nicola Roxon about the incident on Friday when the pair are both scheduled to speak at the Commonwealth Regional Law Conference in Sydney.
DFAT said it was not aware of any Australian government restriction applying to Ms Robinson's travel.
"As an Australian with a valid passport, she would be free to return to Australia at any stage," the spokesman told AAP.
"The UK border authorities or airline of travel may be able to provide further insight on claims that she was impeded from boarding her flight."
The Department of Immigration denied any Australian agency manages an "inhibited list".
"No Australian agency prevented Ms Jennifer Robinson from boarding her flight at Heathrow Airport in London earlier today," the department said in a statement.
Australian Greens senator Scott Ludlam called on Foreign Minister Bob Carr to explain the purpose of the list, who compiles it and whether Ms Robinson's legal representation for Mr Assange was connected to her being on a list.
Senator Ludlam vowed to pursue the matter when parliament resumes in May.
Australian Lawyers Alliance national president Greg Barns said he was gravely concerned by Ms Robinson's experience.
"Simply because a lawyer is representing a client that government does not like, the lawyer is then subjected to security scrutiny," he said.
"Lawyers must be able to act for their clients without fearing that they will be harassed by government agencies, either in their own country or overseas."
theaustralian.com.au 19 Apr 2012
Another typical example of how a 'regime' operates.
Anyone 'against' any government will get persecuted, as mentioned by Assange's lawyer.
There is a 'blacklist' that exists and it goes to such extents where the rest of your life is effected, your career or employment effected if the authorities wish to take action against you for whatever reason they see fit.
This is a larger problem effecting more people than the corporate media make it out, often blaming the individual, and conjuring up a 'conspiracy theory' rather than saying how it really is.