One of President Trump's nominees to the National Labor Relations Board, the main federal labor law enforcement agency, said he would consider recusing himself from cases before the board if they involved any of Trump's business enterprises.

The nominee, lawyer Marvin Kaplan, did not promise to automatically do it, however.

Sen. Patty Murray, D-Wash., the ranking Democrat on the Health, Education, Labor and Pensions Committee, noted some of Trump's businesses had been before the NLRB facing workplace law violations, including within the last year. She asked Kaplan during a hearing Thursday what he would do should case involving a Trump business came before the board.

Kaplan noted the board operates independently, its five members serve fixed terms and can only be fired for cause so that ought to insulate them from conflicts.

He then added: "When such a case emeges, I can pledge I would consult the ethics officer" to ensure there is no conflict.

"Would you recuse yourself if the ethics officer said to?" Murray asked.

Kaplan said he would "absolutely" accept such a recommendation. "I would never argue with the ethics officer," he said.

Trump nominated William Emanuel and Kaplan, currently chief counsel of the Occupational Safety and Health Review Commission, a federal agency, to fill the remaining two open seats on the NLRB. Emanuel is a shareholder with Littler Mendelson, a management-side law firm that specializes in labor matters, often before the board.