AUSTIN, Texas — The Trump administration plans to abandon the federal government’s longstanding opposition to a key portion of Texas’ toughest-in-the-nation voter ID law, a US Justice Department spokesman said Monday.

It’s a dramatic break from the agency under president Barack Obama, which spent years arguing that the 2011 voter ID law that Texas’ Republican-controlled Legislature passed was intended to disenfranchise poor and minority voters.

Danielle Lang of the Washington-based Campaign Legal Center called the decision an ‘‘extraordinary disappointment.’’

‘‘It’s a complete 180,’’ said Lang, the center’s deputy director of voting rights. ‘‘We can’t make heads or tails of any factual reason for the change. There has been no new evidence that’s come to light.’’

The law requires voters to show one of seven forms of state-approved photo identification; gun permits are acceptable but college IDs are not.

Associated Press