A standoff between Ukraine’s defense minister and the official in charge of procuring weapons threatened to escalate on Monday, stirring dissent in the government at a critical time as it seeks to persuade President Trump to maintain American support for the war against Russia.

The dispute erupted three days ago when the minister, Rustem Umerov, said he would not renew the contract of Maryna Bezrukova, the head of the defense procurement agency, citing “unsatisfactory” results. But on Monday, Ms. Bezrukova said she would remain in her position, pointing out that her contract had been renewed by the agency’s supervisory board and that Mr. Umerov had no right to override that decision.

The agency was established to ensure transparency and efficiency in acquiring arms. Activists and some lawmakers, including a prominent one in President Volodymyr Zelensky’s party, denounced Mr. Umerov’s move as an abuse of power undermining anticorruption efforts.

“The minister’s action is a serious offense against our legislation and corporate governance,” Ms. Bezrukova said in an interview over the weekend, calling it an “attack” on the agency’s efforts to cut out questionable intermediaries Ukraine has sometimes relied on to buy weapons during the war.

She reported to her office on Monday, and it was unclear how the standoff would be resolved.

The dispute threatens to weaken an organization that managed over $7 billion in weapons procurement last year and had become a partner for Western allies channeling funds into Ukraine’s growing defense industry — a new initiative Kyiv aims to develop as an alternative for dwindling arms supplies from the West.

Western diplomats in Kyiv were meeting with government and agency officials on Monday to discuss the procurement situation, according to several attendees, who spoke anonymously to discuss private deliberations. Meanwhile, the head of the Ukrainian parliament’s anticorruption committee has called for Mr. Umerov’s resignation.