Dozens of human rights groups and migrant advocates signed a letter Friday warning a possible agreement to designate Guatemala as a safe country for U.S. asylum seekers could put thousand of migrants in danger.

The groups — from Mexico, El Salvador and Guatemala — signed the letter saying what would be known as a “safe third country” agreement between Washington and Guatemala would violate the rights of migrants because Guatemala lacks the resources to guarantee migrants safety and has a low-capacity asylum system. 

"Signing an agreement of this nature represents a grave risk for migrants and asylum applicants because it violates the international obligations the United States and Guatemala would be agreeing to," the letter said. It includes signatures from members of the Migration Policy Task Force in Mexico, the Independent Monitoring Group in El Salvador and the Cross-Border Migration and Gender Round Table in Guatemala.  

President Trump tweeted last month that a safe third country agreement with Guatemala was in the works. The White House in a statement Friday said that Guatemala President Jimmy Morales was scheduled to visit Washington on Monday to discuss migration and security issues. 

The agreement would mean Hondurans, Salvadorans and people from elsewhere who cross into Guatemala would have to apply for asylum there, rather than continuing to the U.S. border. The agreement could ease the crush of migrants at the Mexico-U.S. border, but human rights observers and academics said Guatemala is in a poor position to offer safety and employment when thousands of its own citizens are also fleeing to the United States. 

Three of Guatemala’s former foreign ministers are asking the country’s Constitutional Court to bar Morales from entering into such an agreement, the Associated Press reported.

"We're worried about people who are fleeing violence not being able to have protection within the region,” said Gretchen Kuhner, director of the Institute for Women in Migration, a nonprofit in Mexico City and one of the signers of the letter. “We're worried about the United States not taking any responsibility for the people who are fleeing violence and who are refugees in its own region."