A law allowing gay marriages across Canada could come into force as early as tonight after the Senate overwhelmingly approved the legislation.
That would make Canada the fourth country in the world after Belgium, the Netherlands and Spain to permit same sex marriages, although a number of Canadian provinces have been allowing same-sex marriages for some time.
The unelected Senate upper chamber - dominated by members from the ruling Liberal party - voted by 47 to 21 late yesterday to pass the law.
The lower house of Parliament had already backed the legislation despite fierce opposition from conservative politicians and from religious groups, who portrayed it as an attack on organized religion.
The law needs to be formally approved by Governor-General Adrienne Clarkson, but CBC radio said that could come as early as today.
The Liberal government said it had to draw up the legislation to allow same-sex marriage after courts in eight of the country's ten provinces ruled that failing to do so would violate Canada's Charter of Rights and Freedoms.
Opponents fear churches and religious officials could be sued for refusing to carry out same sex marriages.
The legislation grants gays and lesbians the right to full civil marriages, but makes clear that religious officials would not be obliged to marry same-sex couples.
Some Canadian provinces have already become something of a tourist destination for gay couples from other countries who are seeking to get married.
Canadian residency requirements are less strict than those in other countries that allow gay marriage, but the new unions may not be recognized in the couples' home countries.