Maltese citizen, Alex Vella who has lived in Australia for about 40 years, may not be able to return to his western Sydney home after flying out to Japan because his resident return visa expired in January.

54-year-old Rebels bikie gang leader Alex Vella, recently flew to Japan with his middleweight boxer son Adam Vella, who fought against Japan's Koji Sato in Tokyo on Saturday night. A spokeswoman for Australian Immigration Minister Kevin Andrews said Mr Vella would be unable to return while the application was assessed, which could take "quite some time".

According to The Herald Sun, Mr Vella has been of interest to Australian state and federal law enforcement agencies in the past. The newspaper reported that in 1995 he was convicted of possessing a trafficable quantity of cannabis in his home. Later, his property was raided by police representing state and national crime authorities, who seized and froze his assets.

Mr Vella later was returned these assets after paying a  settlement to the New South Wales Crime Commission.

Mr Vella's wife, Heather, and his sons, Adam and Alex Jr, are all Australian citizens but Mr Vella never applied for citizenship. One of the criteria for a visa application assessment is that the applicant is of good character. According to The Daily Telegraph, Mrs Vella has accused the Federal Government of lying to him.

The Daily Telegraph further reported that the Department of Immigration will argue that Alex Vella's position as the national president of Australia's largest outlaw motorcycle gang means he does not pass the good character test.