The letter, first published by the Mexican newspaper Reforma, states that the U.S. and Mexico "will immediately begin discussions to establish definitive terms for a binding bilateral agreement to further address burden-sharing and the assignment of responsibility for processing refugee claims of migrants."

ADVERTISEMENT The document, signed and dated June 7, states that under such an agreement both countries would commit to "accept the return and process refugee status claims, of third-party nationals who have crossed that party's territory to arrive at a port of entry or between ports of entry of the other party."

It adds that if the U.S. determines after 45 days from the joint declaration reached last week that the measures adopted by Mexico "have not sufficiently achieved results in addressing the flow of migrants to the southern border" then Mexico will take steps to bring the agreement into force within another 45 days.

Marcelo Ebrard, Mexico's top diplomat, presented the document to the Mexican Senate on Friday and said there was no other agreement from the negotiations with the U.S., Reforma reported . Ebrard has said the two sides will reassess the migrant situation after 45 days and again after 90 days.

Well, Mexico just released the full page that @realDonaldTrump carried when he said there was a secret agreement pic.twitter.com/A5ocd4WV6p — Carlos Manuel Rodríguez (@carlos_rgz) June 14, 2019

Trump on Tuesday had held up a single folded sheet of paper in front of cameras before leaving on a trip to Iowa, saying the paper represented an agreement between the U.S. and Mexico.

The president declined to share any details about the letter. He has sought to sell the deal reached between his administration and Mexico amid reports it included actions Mexico had already agreed to take.

"That’s the agreement that everybody says I don’t have," Trump told reporters at the White House on Tuesday while pulling the document from the pocket of his jacket.

"This is one page of a very long and very good agreement for both Mexico and the United States," he added.

Mexico and the U.S. reached a deal late last week for Mexico to take steps to curb the flow of migrants traveling toward the United States's southern border in exchange for Trump dropping his threat to impose a 5 percent tariff on all Mexican goods entering the U.S.

The Hill has reached out to the White House for comment on the letter released Friday.

Rafael Bernal and John Bowden contributed reporting