Protesters will confront Hun Manet, eldest son of Prime Minister Hun Sen, when he arrives in Australia today, according to a statement released by the Cambodian-Australian Federation.

The organisers, including a Victorian politician, called on “Victorian Cambodian Australians” and “friends of the community” to confront the scion, a three-star general, outside an event in Clayton South in Melbourne’s east at 6pm.

The group said the celebration to welcome Manet was “insulting” given that they were preparing to observe the 100th day of mourning since the July 10 murder of political analyst Kem Ley.

“Such provocation from this brutal regime, which most Cambodians believe to have been implicated in the cold blood murder of Dr Kem Ley, is unacceptable,” the statement said, adding that demonstrations would also be held in Sydney and Adelaide.

A woman helping to organise the protest in Melbourne, but who declined to be named, claimed that she expected 500 people to turn out.

Lim, a state parliamentarian in Victoria, was banned from returning to his native Cambodia in August after calling the government a “beast” in the wake of Ley’s death.

Prior to departing, Manet told reporters that Lim and the group had the right to express themselves, but called for them to be respectful.

“I am not concerned about it [the demonstration] because it is not first time . . . When I was in US, there were many times,” Manet added, referring to several demonstrations he faced during a visit in April.