Ottawa - Canada's immigration minister Chris Alexander on Wednesday unveiled plans to ban entry to migrants who practice polygamy and what he termed "barbaric cultural practices".The move follows a spate of so-called "honour" killings over the past decade involving immigrant families from the Middle East and South Asia."We are strengthening our laws to protect Canadians and newcomers to Canada from barbaric cultural practices", Alexander said in a statement."We are sending a strong message to those in Canada and those who wish to come to Canada that we will not tolerate cultural traditions in Canada that deprive individuals of their human rights."The sweeping changes to Canada's immigration act would also prohibit forced marriages, set a minimum age for marriage at 16 and limit possible defences in "honour" killings and many spousal murders.In "honour" killings, carried out to protect what is seen as family pride, reasons for disapproval can include having relationships outside of one's caste or religion.In May, a court ordered the mother and uncle of a Canadian woman allegedly killed overseas over her secret marriage to a poor rickshaw driver to be extradited to India to face prosecution for murder and conspiracy to commit murder in the 14-year-old case.In another case, the father and brother of a 16-year-old girl pleaded guilty in 2010 to murdering her for disobeying her father, including refusing to wear a hijab. The family had moved from Pakistan.