Jean-François Copé, is the leader of the centre-right Union for a Popular Movement and also mayor of Meaux, a town near Paris.
According to a report in The Independent Mr Copé described the marriage law reforms as a left wing threat to the “pillars of our society”.
Mr Copé has also suggested that if he becomes party president next month he will call on all right-wing voters to stage mass protests in order to protect “the future of French children”. He believes that he can enact the same change seen following protests in 1984 over the abolition of Catholic schools, which successfully stopped legislation in their tracks.
Across France there is a growing movement against same-sex marriage, especially in more rural areas of the country. A large number of mayors and their deputies have signed a petition asking for a conscience clause, which would allow them to refuse to perform same-sex marriages.
The debate over same-sex marriage in France is also wrapped up in further legislation looking to give same-sex couples equal rights to adopt children.
Many of the centre-right and right wing opposition to the proposed legislations have focused on the implications the laws may have on the traditional French family, rather than on same-sex marriage itself.
The first reading of the proposed bill is due to take place in the National Assembly at the beginning of December.