Two of the law firms that reached deals with President Trump this year to avoid punitive executive orders were connected in recent months with the Commerce Department about working on trade deals, according to three people briefed on the matter.

The firms, Kirkland & Ellis and Skadden Arps, were connected to the department by Mr. Trump’s personal lawyer, Boris Epshteyn, two of the people said.

Mr. Epshteyn, who does not hold a government position, played a direct role in brokering the initial deals between Mr. Trump and the law firms, in which the firms agreed to do pro bono work on causes the president has championed, like helping veterans, military families and first responders.

His previously undisclosed efforts connecting the firms with the Commerce Department shows how he is seeking to impose Mr. Trump’s expansive view of the deals, including recruiting firms to work for the government in advancing the administration’s agenda.

After Mr. Epshteyn helped connect the firms with the government in recent months, Kirkland and Ellis went on to work on the trade deals the administration struck with Japan and South Korea, which were announced in July, according to three of the people. It is unclear if Skadden Arps has done work for the administration.