Nancy Pelosi (right), speaker of the United States of House of Representatives with Richard Neal (left,) Chair to the House Ways and Means Committee.

House Democrats and the Trump administration did not come to an agreement on moving forward with President Donald Trump's new North American trade deal during a meeting Thursday.

Lawmakers and the White House have worked for weeks to resolve Democratic concerns about enforcement tools for labor and environmental standards under the deal, known as the United States-Mexico-Canada Agreement. Leaving a meeting with House Speaker Nancy Pelosi and U.S. Trade Representative Robert Lighthizer, House Ways and Means Committee Chairman Richard Neal said the sides made progress but did not strike a final agreement, his office confirmed.

A spokesman for Pelosi said the meeting, which lasted more than an hour, was "productive."

"Progress was made in narrowing the differences, and work continues. We can reach an agreement on USMCA when the Trade Representative makes the agreement enforceable for American workers," the spokesman said.

Neal told reporters it is "possible" the House could vote on USMCA, Trump's replacement for NAFTA, by the end of the year. Before the Democrats huddled with Lighthizer, Pelosi told reporters that "I'm not even sure if we came to an agreement today that it would be enough time to finish" before 2020.