A family law expert said that if the man, identified only as Mr. G, successfully regains custody of his children, his case could revolutionize the Irish court system in relation to unmarried fathers, The Irish Times said Wednesday.

The man alleges his former wife took their 2-year-old twin sons to Britain without his consent and in violation of Hague Convention terms.

The convention states that a parent must be a child's legal guardian to claim parental responsibility, the newspaper said.

Mr. G argued he was not given the opportunity to seek guardianship rights under Irish law before his ex-wife took the children out of the country.

Unmarried Fathers of Ireland spokesman Donnacha Murphy said the case could result in a landmark ruling.

"The facts of this case would appear to constitute an ideal case for the consideration of discrimination within Irish family law legislation," he told the Times.