Portuguese President Anibal Cavaco Silva will veto a gay marriage bill approved by lawmakers in February, Radio Renascenca reported.

Cavaco Silva will veto the bill soon after Pope Benedict's arrival on May 11.

Last month, the president, a Roman Catholic and a member of the PSD party, groups which oppose the legalization of gay marriage, forwarded four out of five of the bill's articles to the country's Constitutional Court, setting aside a measure that prohibits gay adoption. He said he did so because he doubted the bill's constitutionality, but refused to say why he did not include the article on adoption.

The court's majority, however, ruled the four articles to be constitutional earlier this month.

The president has 20 days from the ruling's official publication – which has yet to occur – to either reject the measure or allow it come into force.

Opposition to the gay marriage bill in the Roman Catholic stronghold of Portugal has been mostly muted, but Pope Benedict's impending visit has already reignited opposition to the bill and likely played a role in influencing the president's decision. In neighboring Spain, Benedict has called for the ouster of Socialists who approved a gay marriage law in 2005.

In January, Benedict took a swipe at countries considering legalizing gay marriage, saying it threatens creation.

“Creatures differ from one another and can be protected, or endangered in different ways, as we know from daily experience,” he told diplomats who had gathered at the Vatican. “One such attack comes from laws or proposals, which, in the name of fighting discrimination, strike at the biological basis of the differences between the sexes.”

“I am thinking, for example, of certain countries in Europe or North and South America,” he added.

Social Democrats – led by Prime Minister Jose Socrates – say they have the votes needed to override the veto.

If the bill is approved, Portugal would join five European countries – Spain, Belgium, the Netherlands, Norway and, most recently, Sweden – in legalizing gay marriage.