WASHINGTON — Congressional Democrats are examining whether a former arms-industry lobbyist serving as a midlevel State Department official played a role in the Trump administration’s decision last month to sell weapons to Saudi Arabia and the United Arab Emirates without seeking legislative approval, lawmakers and current and former government officials said.

A House committee plans to question a senior State Department official on Wednesday over the sales, and in particular over the role of Charles Faulkner, who worked until recently in the department’s legislative affairs bureau, congressional aides said. Before joining the State Department, Mr. Faulkner worked for four years for a firm in Washington that lobbied for Raytheon Company, whose precision-guided bombs are a significant part of the arms packages to the gulf and had been blocked by Democratic lawmakers.

Lawmakers from both parties are still furious at the decision by President Trump and Secretary of State Mike Pompeo in late May to use a loophole in legislation to push through more than $8 billion worth of weapons sales, almost all to the gulf nations. The two countries are leading an air war against rebels in Yemen that has resulted in a humanitarian disaster and thousands of civilian deaths, many of them children.

Lawmakers from both parties are also reviewing ways to block the arms sales, much of which they had held up since last year.