WASHINGTON — The federal government on Friday announced regulatory changes to extend a wide range of marriage benefits to same-sex couples, making good on a promise by President Obama after the Supreme Court struck down the Defense of Marriage Act last year.

The Department of Labor said it would clarify that federal employees will be able to take leave from their jobs to care for a same-sex spouse, something that has long been limited to heterosexual married couples. The Social Security Administration and the Veterans Affairs Department said they would also expand benefits for same-sex couples, subject to some legal restrictions.

After decades of blocking gay married couples from receiving the same benefits as their heterosexual counterparts, most federal agencies are now treating married couples alike, regardless of gender.

The actions are important, officials said, because of differences in how states treat same-sex marriage. Without the regulatory changes, same-sex couples could be blocked from receiving federal benefits in states that do not recognize their marriages. Same-sex marriage is legal in 19 states and the District of Columbia.