Story highlights German lawmakers will vote on same-sex marriage this week

Chancellor Angela Merkel said Monday she would like to see "vote of conscience" on the issue

Germany lags behind many other countries on gay rights

(CNN) German lawmakers will decide Friday whether to legalize same-sex marriage, according to CNN affiliate NTV. The snap vote comes after Chancellor Angela Merkel said Monday that she would like to see parliament move towards a "vote of conscience" on the issue.

Following Merkel's comments, German politicians writing on Twitter called for a vote to be held as soon as possible. Martin Schulz, leader of the Social Democratic Party (SPD) -- the second largest party in parliament -- called for parliament not to wait until after the federal election in September. "We will push through marriage equality in Germany," he tweeted. "This week."

Wir werden die Ehe für alle beschließen. Diese Woche. — Martin Schulz (@MartinSchulz) June 27, 2017

The vote is likely to pass with strong support from other German parties and from some lawmakers within Merkel's CDU. Volker Kauder, leader of the parliamentary group of the ruling CDU faction, called Tuesday for CDU members voting for and against the law to show respect for each other's position, according to NTV. But he also warned that such a sudden vote could lead to a "hasty decision."

Merkel's comments on Monday represent a shift for the German leader and her conservative party, the Christian Democratic Union (CDU), which has opposed same-sex marriage to keep in line with "traditional" family values.

The Chancellor made the comments in response to a question Monday evening at an event in Berlin hosted by women's magazine Brigitte. Asked by a gay man in the audience whether he would be able to refer to his partner as "my husband," Merkel acknowledged the widespread support for gay marriage among German voters -- who will vote soon in federal elections -- and suggested a free vote on same-sex marriage could be held among members of parliament.

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