Argentina yesterday became the first country in Latin America to legalise same-sex marriage, following a landmark Senate vote carried live on national television.

The law, backed by the centre-left government of President Cristina Kirchner, was adopted in a 33-27 vote after 15 hours of debate. In this majority Roman Catholic country, some had reservations, but the law passed.

"It is a historic day," said ruling party leader Miguel Pichetto.

Opposition Radical senator Gerardo Morales said Argentine society has changed, stressing that the Bill was aimed at guaranteeing the rights of minorities.

Hundreds of people outside Congress cheered when the Bill passed. Some chanted "Equality, Equality". Some tearful couples embraced.

In a country where more than 90 per cent of people describe themselves as Catholic, some protestors including priests showing images of the Virgin Mary prayed outside as lawmakers took up the legislation.

Some marchers with gay and leftist groups shouted "Church, you garbage, you are a dictatorship."

On Wednesday police had to separate opposing groups protesting outside the Senate who hurled eggs and oranges at each other.

Former President Adolfo Rodriguez Saa said: "Argentina has taken a step forward, but out in the street ... it will take time for hatred and resentment to heal."

The Catholic Church had called unsuccessfully for a national referendum on the issue.

Mr Kirchner on Monday criticised Church arguments, saying they brought to mind "the Inquisition".