In a major victory for same-sex marriage rights, the Justice Department will soon grant married gay and lesbian couples the same rights in legal matters as other married couples.

The new policy announced by Attorney General Eric Holder on Saturday evening in New York, marks the latest step by the Obama administration to extend rights to same-sex couples that are afforded to married, heterosexual couples.

“In every courthouse, in every proceeding and in every place where a member of the Department of Justice stands on behalf of the United States, they will strive to ensure that same-sex marriages receive the same privileges, protections and rights as opposite-sex marriages under federal law,” Holder said in prepared remarks to the Human Rights Campaign, an advocacy group that works on behalf of lesbian, gay, bisexual and transgender equal rights.

The Justice Department will issue a memo Monday to its employees instructing them to give lawful same-sex marriages full and equal recognition to the greatest extent possible under the law. Gay marriage is currently legal in 17 states and the District of Columbia.

Holder, the first African-American attorney general, has frequently compared the struggles of extending rights to same-sex couples to the civil rights movement in the 1960s, a reference he made again Saturday.

“Just like during the civil rights movement of the 1960s, the stakes involved in this generation’s struggle for LGBT equality could not be higher,” Holder said in prepared remarks. “Then, as now, nothing less than our country’s commitment to the notion of equal protection under the law was on the line.”

Under the new guidelines, same-sex couples would not be forced to testify in court against their spouse and would receive the same visitation rights as other married couples in prison. The Justice Department’s policy will also allow same-sex married couples to apply for federal programs such as the Sept. 11 fund to compensate victims of the terrorist attacks.

“This policy has important, real-world implications for same-sex married couples that interact with the criminal justice system,” Holder said.

Opponents of gay marriage were quick to criticize the Obama administration.

In a statement, Tony Perkins, president of the Family Research Council, said the extension of federal benefits, even in states that do not recognize same-sex couples, “is yet another illustration of the lawlessness of this administration.” Perkins said the Justice Department’s decision highlights the need for Congress to pass legislation that would require federal agencies to only recognize gay and lesbian marriages in states where it is legal.

Sandy Rios, director of governmental affairs for American Family Association, also lambasted the latest move.

“While the Holder Justice Department has no time to investigate Fast and Furious or Benghazi, where Americans lost their lives, it has plenty for gay ‘rights,'” she said. “I guess you could say money and privilege for homosexuals trumps life and liberty for other Americans.”

Chad Griffin, president of the Human Rights Campaign, said the “landmark announcement” will improve the lives of gay and lesbian couples.

“While the immediate effect of these policy decisions is that all married gay couples will be treated equally under the law, the long-term effects are more profound,” Griffin said. “Today, our nation moves closer toward its ideals of equality and fairness for all.”

“This is just the latest in a series of moves by the Obama administration, and in particular the Department of Justice, to undermine the authority and sovereignty of the states to make their own determinations regulating the institution of marriage,” said Brian Brown, president of National Organization for Marriage. “The changes being proposed here to a process as universally relevant as the criminal justice system serve as a potent reminder of why it is simply a lie to say that redefining marriage doesn’t affect everyone in society.”

The Justice Department’s new policy is the latest in a series of victories for same-sex marriage supporters. The foundation for Holder’s announcement was established by a pair of rulings from the Supreme Court in June that boosted gay and lesbian rights when it upheld a California ruling legalizing same-sex marriage in the nation’s most populous state and struck down a federal law that denied benefits to same-sex couples who were already married.