(CNN) - The Trump administration moved Thursday to jumpstart the approval process for President Donald Trump's replacement for the North American Free Trade Agreement, applying further pressure on House Democrats to consider the trade plan.
US Trade Representative Robert Lighthizer submitted the White House's draft statement of administrative action — a summary of legal changes required to comply with the US-Mexico-Canada Agreement — to Congress on Thursday, a USTR spokesperson said.
The move starts a 30-day clock for House Democrats and the administration to come to an agreement on the text of a bill enacting Trump's deal. After 30 days, the White House will be able to submit legislation of the deal for Congress to consider, but it is not required to.
The administration wants to ratify the agreement before the end of the year, and Thursday's move would set up a vote in the fall if Trump puts forward the legislation.
The move drew a quick reply from House Speaker Nancy Pelosi, who had warned the White House not to move forward yet as Democrats seek changes on key aspects of the agreement.
"The Trump Administration's decision to send Congress a draft statement of administrative action before we have finished working with US Trade Representative Lighthizer to ensure the USMCA benefits American workers and farmers is not a positive step," Pelosi said in a statement. "It indicates a lack of knowledge on the part of the administration on the policy and process to pass a trade agreement."
Democrats have raised key environmental and labor concerns with the new trade deal, with some calling on Trump to reopen negotiations entirely.
Lighthizer, in his letter to Pelosi, acknowledged that outstanding issues remain for members of Congress.
"Submission of the draft SAA does not limit our ability to find solutions to address concerns Members have raised about enforcement of the labor and environmental provisions of the Agreement and pharmaceutical pricing," wrote Lighthizer, who has consistently said that he believes Democrats will get on board with the deal. "We are confident those concerns can be addressed to the satisfaction of the vast majority of Members from both parties through the implementing legislation or otherwise."
A senior administration official told CNN some White House aides believed they needed to apply more pressure on Pelosi to move the process forward, leading to Thursday's decision. The move wasn't universally supported in the West Wing — some officials argued Trump should continue negotiating with Democrats to generate more support in Congress beforehand, as Pelosi had urged.
A Democratic aide said the decision caught members by surprise on Thursday afternoon, when Lighthizer called key congressional offices to inform them the administration would be moving forward.
The aide said it could frustrate Democrats who have urged Trump not to rush the deal, as well as complicate talks between the White House and Congress. Pelosi was expected to finalize by Friday members of four groups of Democrats who will be negotiating the text of the deal with Lighthizer.
The White House did not immediately reply to a request for comment. The move was first reported by the Washington Post.
The decision comes as Vice President Mike Pence is in Canada, where legislators there are taking steps to begin ratifying the deal, which was signed late last year by the leaders of all three participating nations.
"The President and I are absolutely determined to work with rank and file in the Congress, and the leadership, to move the USMCA forward and to move it forward this summer," Pence said during a joint press conference with Canadian Prime Minister Justin Trudeau.
He said Lighthizer would be meeting with lawmakers next week, when they return from a congressional recess, to discuss implementation legislation for the trade package.
"We remain confident that the USMCA will receive broad-based support in the Congress if it's brought to the floor," Pence said. "And to that end we're reaching out to members of Congress."