The White House’s trade representative in late August withdrew a recommendation to restore some of Ukraine’s trade privileges after John Bolton, then-national security adviser, warned him that President Trump probably would oppose any action that benefited the government in Kyiv, according to people briefed on the matter.

The warning to Robert E. Lighthizer came as Trump was withholding $391 million in military aid and security assistance from Ukraine. House Democrats have launched an impeachment inquiry into allegations that the president did so to pressure Ukrainian President Volodymyr Zelensky to investigate the business activities of former vice president Joe Biden’s son Hunter Biden. As part of the inquiry, lawmakers are closely scrutinizing the White House’s actions between July and September.

The August exchange between Bolton and Lighthizer over the trade matter represents the first indication that the administration’s suspension of assistance to Ukraine extended beyond the congressionally authorized military aid and security assistance to other government programs. It is not clear whether Trump directed Bolton to intervene over Ukraine’s trade privileges or was even aware of the discussion.