/ Updated  / Source: Reuters

MANILA — Philippine President Rodrigo Duterte's top ally in Congress proposed new bills to legalize divorce and same-sex unions on Monday, a move almost certain to meet fierce resistance from bishops in the mainly Catholic country.

Opening the lower house for its second regular session, Speaker Pantaleon Alvarez said he would file a bill to legally recognize civil partnerships between people of the same sex. The Philippines would become the first Southeast Asian nation to legalize same-sex unions if he succeeds.

Pantaleon Alvarez, Speaker of the House of Representatives, strikes the gavel to signal the opening of the Second Regular Session of the 17th Congress at the House of Representatives in Quezon City, Philippines, 24 July 2017.Rolex Dela Pena / EPA

Alvarez said citizens should be allowed to divorce legally as much as same-sex couples should be allowed to have legally recognized unions.

"We must also be considerate of the fact that marriage may not be for everyone," he said.

"Presently, it even excludes certain groups of people from its fold. Our citizens should not be excluded from society just because of the person they love. They must also be treated with equality before the law," he said.

Twenty-seven countries, mostly in Western Europe and the Americas, have already recognized same-sex unions. A court in Taiwan issued a ruling in May that said same-sex couples had the right to marry legally.

The Vatican and the Philippines are the only states in which divorce is outlawed.

The proposals by Alvarez drew mixed reactions from lawmakers, both allies and the opposition.

The Philippine bishops would most likely try to block moves to legalize divorce and same-sex marriages, although Catholic Church representatives were not immediately available for comment.

Related: Asia’s Youngest Nation Offers Glimmer of Hope for LGBTQ Rights

Congressman Teodoro Baguilat described the proposal as "bold, clear and progressive", but representative Tom Villarina said Congress should focus on passing an anti-discrimination bill put forward by the lesbian, gay, bisexual and transgender community because that proposal already had broad support.

In the most recent opinion polls, Filipinos overwhelmingly rejected same-sex marriages, with the latest survey in 2015 showing nearly 70 percent of 1,200 respondents strongly disagreed. Laws on same-sex marriages have been proposed as far back 2006, but none has gained traction.

However, the latest attempt could gain momentum because it has the endorsement of Alvarez, a close ally of Duterte, who enjoys a super-majority in the legislature.

Alvarez said divorce would strengthen the rights of minors, because there would be fewer illegitimate children under the law. Divorces, he said, would be a far less tedious and expensive process than annulling marriages, which can take years and face many legal hurdles.

"They (would) no longer have to sling mud at each other in front of a judge just to convince the magistrate that their marriage should be declared void," he said.

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