MEXICO CITY (Reuters) - Mexico is opposed to a U.S. request to make people seeking asylum in the United States apply in Mexico instead, according to a source and a briefing note, in a setback to U.S. efforts to deepen cooperation on immigration before a leftist president takes office.

FILE PHOTO: Members of a caravan of migrants from Central America, enter the United States border and customs facility, where they are expected to apply for asylum, in Tijuana, Mexico May 4, 2018. REUTERS/Edgard Garrido

U.S. officials believe a deal known as a “Safe Third Country Agreement,” could prove a deterrent to thousands of Central Americans who travel through Mexico each year to seek U.S. asylum, clogging immigration courts and causing a headache for U.S. President Donald Trump’s administration.

Yet despite growing U.S. pressure for it to accept the treaty, Mexico views the proposal as a red line it will not cross, according to the briefing note prepared for Foreign Minister Luis Videgaray for a meeting he had with U.S. Homeland Security Secretary Kirstjen Nielsen in Guatemala on Tuesday.

“Mexico is not in the position to accept a safe third country agreement, as the United States has proposed on previous occasions,” the note says.

“Mexico has made a significant effort to provide Central Americans detained on (Mexico’s) southern border with greater information on asylum, and recently adopted measures which allow asylum applicants to work while their case is resolved.”

The safe third country proposal would force asylum-seekers who arrive at the U.S. land border via Mexico to apply to stay in Mexico, likely as refugees south of the border.

Many of the 2,000 or so foreign children taken from their parents recently under Trump’s zero-tolerance policy against illegal immigration were separated from parents seeking asylum in the United States.

LOPEZ OBRADOR COMING

Under Videgaray, Mexico has become increasingly willing to cooperate with United States on some issues, which senior U.S. and Mexican officials say is part of a strategy to curry favor with Washington in hopes of winning a beneficial renegotiation of the North American Free Trade Agreement.

The United States is hoping to consolidate improved cooperation on immigration and security before leftist Andres Manuel Lopez Obrador is sworn in as Mexican president on Dec. 1, according to officials from both countries.

While Lopez Obrador says he wants good relations with the United States, the nationalist-leaning leader is a long-term advocate of migrant rights and is seen as even less likely to accept an asylum pact, a senior Mexican official said.

The Mexican official, who asked to speak anonymously to discuss private bilateral discussions, said it was not clear whether Nielsen had proposed the agreement in her bilateral meeting with Videgaray, nor whether the Mexican minister rejected it if she did.

Nonetheless, the official said there was no indication of a change in Mexico’s policy following the meeting.

The U.S. State Department referred questions to the Department of Homeland Security, which did not respond.

“We are interested in dealing with the fact that both Mexico and the United States are facing a sharp increase in refugee requests and addressing the root causes of migration through development,” Mexico’s ambassador to the United States, Geronimo Gutierrez, said in a statement when asked for Mexico’s position on the request.

“We constantly engage in dialogue with our U.S. counterparts on these matters to identify and develop areas of cooperation.”

Both Videgaray and Lopez Obrador will meet U.S. Secretary of State Mike Pompeo when he visits Mexico on Friday along with Nielsen.

Mexico’s foreign ministry declined to say whether the asylum proposal would be on the agenda in those meetings. A spokesman for Lopez Obrador’s foreign policy team did not respond to a request for comment.

Lopez Obrador is expected to suggest in the meeting that the United States help to reduce migration by helping create better living standards in Mexico and Central America.