Gay and lesbian couples began marrying in Switzerland on Friday as a new marriage law took effect.

After lawmakers approved the “Marriage for All” bill in 2020, opponents quickly gathered enough signatures to put it on the ballot.

Swiss voters in September overwhelmingly approved the “Marriage for All” law.

Switzerland has recognized gay couples with registered partnerships since 2005. But marriage includes additional rights, such as the joint adoption of children.

The U.S. Embassy in Switzerland on Friday cheered the news.

“Today we celebrate marriage for all,” the embassy tweeted. “Congratulations to Switzerland on this historic day.”

Scott Miller, the U.S. ambassador to Switzerland and Liechtenstein, is openly gay. He is married to Tim Gill, the founder and co-chair of the Gill Foundation, an LGBTQ rights organization based in Denver.

Switzerland began recognizing same-sex marriages from other countries in January.

Legislation to extend marriage rights to same-sex couples in Switzerland was first introduced in 2013.