U.S. Trade Representative Robert Lighthizer gestures as he speaks during a meeting at the Presidential Palace, in Mexico City, Mexico December 10, 2019.

U.S. Trade Representative Robert Lighthizer acknowledged on Sunday the White House had to make concessions in order to sign its USMCA trade agreement.

"We had an election and the Democrats won the House," he said, when CBS' Margaret Brennan asked about wins the Democrats were claiming in their negotiation of the bill.

"It was always my plan and I was criticized for this, as you know, it was always my plan that this should be a Trump trade policy. And a Trump trade policy is going to get a lot of Democratic support."

The White House last week reached an agreement with House Democrats to move forward with its replacement of the North American Free Trade Agreement. The United States-Mexico-Canada Agreement was more than a year in the making, as Republicans and Democrats fought over protections for labor, the environment, intellectual property and the digital economy.

The Democratic-controlled House could vote to ratify the bill before the end of the year

Trump last week called the bill the "best and most important trade deal ever made by the USA." House Speaker Nancy Pelosi said the deal was "infinitely better" than what the administration originally proposed.

"This bill is better now with the exception of biologics, which is a big exception," said Lighthizer.