Gay rights groups are criticising the Vatican this week over a debate on how to block the spread of laws in traditionally Roman Catholic countries granting legal status to homosexual marriages.

Theologians and jurists are taking part in the five-day seminar at the Vatican-administered Lateran university in Rome, organised by the John Paul II institute for Studies of Marriage and the Family.

Italian gay rights group Arcigay criticised the meeting, they told Italian daily la Republica the Vatican “is confirming itself as the biggest organisation in the world opposed to equal rights for homosexuals.”

The seminar demonstrates the growing concern within the Roman Catholic Church over the increasing number of countries giving legal status to homosexual marriages, which Pope Benedict XVI has described as a “serious error”.

Laws allowing gay marriage have been introduced in five countries, Belgium, Britain, Canada, the Netherlands and Spain, and many others, including France, recognize the rights of non-married couples.

The institute’s president, Monsignor Livio Melina said: “The gay movement is a powerful cultural lobby which is very pervasive in intellectual and leadership circles. Its objective is to destroy a certain conception of the family.”