A US district court, in a setback for President Donald Trump, struck down a congressional map on Tuesday redrawn by Republicans in Texas that was intended to give the party five more likely seats in the House of Representatives.

The court ruled that the new map, which weakened five Democratic districts, could not be used in the 2026 midterm elections, where Republicans are seeking to safeguard their slim majority in the House.

Democrats are eyeing a big win that would allow them to challenge the Republican president for the rest of his term.

The court said the redrawn map, which was challenged by Black and Hispanic voters, amounted to illegal racial gerrymandering.

In a split 2-1 decision, the court ordered Republican-ruled Texas to use a 2021 map for next year's congressional midterm vote.

The decision, which Republican Texas Governor Greg Abbott said he would appeal to the conservative-majority Supreme Court, is the latest development in a congressional redistricting battle between Republicans and Democrats playing out nationwide.

Democratic-ruled California, in response to the move in Texas, voted earlier this month to redraw its own congressional districts to favor Democrats, potentially gaining up to five more House seats.

That move has been challenged in court by the Republican Party of California in a lawsuit that has received the backing of the Trump administration.

Republicans in Missouri, North Carolina and Ohio have also moved to create more Republican-leaning congressional districts in their states.

US electoral districts are traditionally drawn following the national census to reflect population numbers. The next census is not scheduled until 2030.

But Republican-ruled Texas, under pressure from Trump, decided to redraw its congressional maps mid-decade to yield more Republican districts.

Republicans currently hold a narrow five-seat majority in the House. They also have a majority in the Senate, preventing Democrats from mounting meaningful opposition to Trump.

District Judge Jeffrey Brown, in the 160-page ruling striking down the Texas redistricting, said "the public perception of this case is that it's about politics."

"To be sure, politics played a role in drawing the 2025 Map," Brown wrote. "But it was much more than just politics. Substantial evidence shows that Texas racially gerrymandered the 2025 Map."

Partisan gerrymandering is allowed in the United States but crafting congressional districts on the basis of race is considered unlawful.

- 'Brazen' -

Brown, a Trump appointee, was joined in the opinion by a district judge appointed by Democratic president Barack Obama. A judge appointed by Republican president Ronald Reagan dissented.

Gene Wu, the leader of the Democratic minority in the Texas state House of Representatives, welcomed the court ruling.

"A federal court just stopped one of the most brazen attempts to steal our democracy that Texas has ever seen," Wu said in a statement.

"Greg Abbott and his Republican cronies tried to silence Texans' voices to placate Donald Trump, but now have delivered him absolutely nothing."

The Texas governor said the state would "swiftly" lodge an appeal with the Supreme Court.

"The Legislature redrew our congressional maps to better reflect Texans' conservative voting preferences –- and for no other reason," Abbott said in a statement. "Any claim that these maps are discriminatory is absurd."

Attorney General Pam Bondi said the Trump administration expects Texas to triumph at the Supreme Court, where conservatives have a 6-3 majority.

"We strongly disagree with today's district court ruling on Texas's redistricting map -- Texas's map was drawn the right way for the right reasons," Bondi said on X.