He says he will refuse arrest on his return, calling instead for the Cambodian people to remove the long-ruling prime minister and 'bring him to justice.'
Sar Kheng says use of military to enforce court orders is excessive.
Cambodia’s government calls the move an interference in its internal affairs.
Found in breach of immigration laws, eight adults deported to Cambodia, three minors held for guidance.
Brussels’ move comes as opposition leader Sam Rainsy warns of perils of China’s growing economic presence in Cambodia.
The group was held for about one month on gambling charges.
The 15 men and three boys were picked up at Islamic schools in an area hit by Muslim insurgency.
His lawyer and rights groups contend that his post was protected under Cambodia’s constitution.
The rejection follows a US intelligence assessment which said a ‘slide toward autocracy’ could see the charter changed.
Hun Sen dares Sam Rainsy to return and warns the West against meddling in Cambodia’s affairs.
They say they need to look after fish farms left behind, and that conditions at a relocation site are inadequate.
Villagers were protesting a court decision to evict them and hand their land to a wealthy businessman.
The offering comes as Phnom Penh bolsters ties with Beijing to counter pressure from the West.
Ex-political prisoner Meach Sovannara says the Cambodia National Rescue Party will remain united despite a crackdown by the ruling party.
Former CNRP members barred from politics may not take part, Cambodian authorities say.
Imports from the two nations had nearly doubled in the past five years, while prices declined.
Meanwhile, two former opposition figures are allowed to re-enter politics after applying to Cambodia's king for a 'pardon.'
But a critic of strongman PM Hun Sen say such a move is conceivable given his ties to her family.
