Democratic Rep. Steve Cohen announced that he planned to retire at the end of the congressional term instead of running for reelection following Tennessee’s adoption of a new map that affected his district.

Tennessee’s 9th Congressional District, a seat which Cohen has held for 19 years, was redrawn earlier this month. And the Cook Political Report moved its outlook for the seat from solidly Democratic to solidly Republican following the change in the map lines.

“This is by far the most difficult moment I’ve had as an elected official,” Cohen said while announcing his decision.

Tennessee’s new map divides Memphis and Shelby County into three districts — dividing up the state’s only majority-Black district. That gives Republicans a high chance of flipping the state’s only Democratic-held seat.

“I considered running one of these three districts, but they’re not Memphis,” Cohen said. “One of them has 12 counties. Two of them go around — one to the Kentucky border, one to the Mississippi border, and go all the way up to a Republican county, south of Nashville, Williamson County. There’s no commonality of issues and purposes between Williamson County and Orange Mound.”

The move follows the Supreme Court’s ruling late last month that gutted a key part of the Voting Rights Act, making it harder to challenge discriminatory voting maps and laws.

U.S. Chief District Judge Chip Campbell has already sided with the state over challenges to the new map. So far, a handful of lawsuits have been filed arguing that the redistricting plan violates the Constitution, is racially motivated and was put in place with too little time before elections.

House Minority Leader Hakeem Jeffries praised Cohen’s work championing his constituents during his nearly two decades on the Hill.

“Steve has consistently stood up for the health, safety and economic well-being of children and families, fighting to lower costs, improve the quality and affordability of higher education, strengthen our transportation infrastructure and increase access to healthcare,” Jeffries said in a statement. “The first Jewish person elected to represent Tennessee in the Congress, Steve has been a powerful champion for civil rights, leading passage of a resolution issuing the first formal apology for slavery in the U.S. As the Chair of the Judiciary Subcommittee on the Constitution, Civil Rights and Civil Liberties, Steve led hearings on the Voting Rights Act, police reform and racial justice, reaffirming his commitment to making true America’s promise of equality and justice for all.”

The new 9th District runs from south Memphis across the southern part of Tennessee before turning north into Marshall, Maury and Williamson counties.

“The GOP’s newly proposed TN Congressional maps would have people in Shelby County all the way to Williamson County—200+ miles apart—being ‘represented’ by the same Congressman,” Cohen wrote on social media at the time the map was proposed. “It’s a blatant, corrupt power grab that would destroy the Black community’s and our entire city’s voice.”

Tennessee state Rep. Justin Pearson, who has been outspoken against the state’s redistricting, is still running in the Democratic primary for the district.

The new map has also drawn Republican candidates. State Rep. Todd Warner and state Sen. Brent Taylor declared their candidacies in the Republican primary for the seat.