President Volodymyr Zelensky of Ukraine was facing growing domestic pressure on Wednesday over a measure to curb the independence of anticorruption agencies, even as he defended it as necessary to root out “Russian influence” in the agencies.

Mr. Zelensky signed into law on Tuesday a bill limiting the independence of two investigative agencies that have been leading efforts to root out corruption. The move has been met with street protests and a rebuke from allies, and it has apparently caused divisions within his government.

The director of Ukraine’s military intelligence agency, Gen. Kyrylo Budanov, one of the most senior security officials in Ukraine’s wartime leadership, posted a rare statement on domestic policy that appeared to criticize the move.

The statement, posted on Facebook on Tuesday, did not directly condemn the law, but General Budanov called for Ukraine to maintain strong “institutions,” particularly during the war. “I am certain that strong armed forces and institutions will save Ukraine,” he wrote. He also called for unity.

In his first public comments on the law, Mr. Zelensky posted a video statement after 1 a.m. on Wednesday calling the measure necessary for removing “Russian influence” from the anticorruption groups. The domestic intelligence agency had on Monday searched homes of investigators, accusing some of having ties to Russia.

“The anticorruption infrastructure will continue to work, only without Russian influence,” Mr. Zelensky said. “That must be cleansed.”