JERUSALEM — Israel’s centrist Yesh Atid Party introduced civil union legislation on Tuesday that would give same-sex couples access to the rights of marriage and free heterosexual ones from the religious strictures imposed on marriage.

Israel has no civil marriages, and some experts estimate that in recent years a quarter of Jewish couples have chosen to either marry abroad or live together without marrying rather than adhere to the chief rabbinate’s requirements for, among other things, proving Jewish ancestry. Hiddush, an Israeli group that promotes religious pluralism, recently placed Israel among the 45 nations in the world with “severe restrictions” on marriage; most of the other 44 are governed by Islamic law.

Arab citizens of Israel are married through either Christian or Islamic authorities, and encounter problems if they wish to marry outside their faith.

Supporters of the rabbinate’s control over marriage, divorce and other family matters say it is essential for the unity of the Jewish people. Jewish law prohibits certain unions — for example, descendants of the ancient tribe of priests cannot marry divorced women — so allowing civil marriage could create problems for religious marriage in future generations.