Rep. Ruben Gallego (D-Ariz.) on Friday slammed newly minted Independent Sen. Kyrsten Sinema (Ariz.) following her decision to leave the Democratic Party, saying she is “putting her own interests” ahead of Arizona voters with the move.

“Last month, the voters of Arizona made their voices heard loud and clear — they want leaders who put the people of Arizona first. We need Senators who will put Arizonans ahead of big drug companies and Wall Street bankers,” Gallego, who is thought to be a 2024 Senate hopeful, said in a statement.

“Whether in the Marine Corps or in Congress, I have never backed down from fighting for Arizonans. And at a time when our nation needs leadership most, Arizona deserves a voice that won’t back down in the face of struggle,” Gallego continued. “Unfortunately Senator Sinema is once again putting her own interests ahead of getting things done for Arizonans.”

Prior to Sinema’s maneuver, Gallego was considered a prime candidate to launch a primary challenge against her in 2024. The House Democrat has been one of the leading critics of Sinema over the past year, including for what he saw as Sinema’s lack of work on behalf of the party in the key state during the 2022 midterms.

Reports also emerged earlier this year that Gallego had met with some of Sinema’s top donors about the possibility of a 2024 bid. News of the meetings came as the Arizona senator stood in the way of two top priorities of leading Democrats: the party’s multitrillion-dollar social spending package and ending the legislative filibuster to pass voting rights legislation.

Criticism also came from other corners of the Arizona Democratic operation, including the state party itself. In a statement, the Arizona Democratic Party said that while Sinema helped with the passage of high-priority items in recent years, she has fallen “dramatically short” on a number of topics, including voting rights, and is “leaving Arizonans behind.”

“Senator Sinema may now be registered as an Independent, but she has shown she answers to corporations and billionaires, not Arizonans,” the party continued. “[Her] party registration means nothing if she continues to not listen to her constituents.”