Robert Lighthizer testifies before a Senate Finance Committee confirmation hearing on his nomination to be U.S. trade representative on Capitol Hill in Washington, U.S., March 14, 2017. REUTERS/Yuri Gripas

WASHINGTON (Reuters) - Republican U.S. Senators John McCain and Ben Sasse said on Wednesday they would vote against President Donald Trump’s nominee for U.S. trade representative, Robert Lighthizer, because of his opposition to the North American Free Trade Agreement.

“Unfortunately, your confirmation process has failed to reassure us that you understand the North American Free Trade Agreement’s (NAFTA) positive economic benefits to our respective States and the nation as a whole,” McCain and Sasse said in a letter to Lighthizer.