Mexico said Thursday it had received an offer from the United States of payment to deport migrants, but denied it had accepted the deal.
The statement followed reports that President Donald Trump's administration planned to send Mexico $20 million to deport undocumented Central Americans crossing its territory toward the United States.
"Regarding the US State Department's notification to Congress of its intent to allocate resources to assist Mexico in repatriating third-country nationals... the Mexican government is still evaluating the proposal," it said.
The New York Times reported earlier that the Trump administration had told Congress it planned to use millions in foreign aid to help Mexico pay for plane and bus tickets to send home up to 17,000 undocumented migrants.
"The Mexican government has not accepted said proposal, verbally or in writing, or signed any document in that regard," said the foreign and interior ministries in a statement.
The plan is Trump's latest move to stop undocumented immigrants from reaching the United States.
He also wants to build a wall on the US-Mexican border -- which he is fond of vowing he will make Mexico pay for, straining the two neighbors' relations.
His "zero tolerance" policy on undocumented immigration led to thousands of children being separated from their parents earlier this year when the latter were arrested.
The resulting outcry at home and abroad forced the administration to backtrack, but 416 of the minors remain in custody despite a court order to reunite them with their parents or guardians.
More than half a million migrants cross into Mexico each year seeking to reach the United States, according to the United Nations.
Most are Central Americans fleeing poverty and brutal gang violence.