President Donald Trump’s plans to seal the U.S.-Mexico border and conduct mass deportations might soon run into a major roadblock: Mexico and the countries where the immigrants come from might not accept some of them back.

When Dayana Castro heard that the U.S. asylum appointment she waited over a year for was canceled in an instant, she had no doubt: She was heading north any way she could.

M ore than any other country, Donald Trump went after Mexico on his first day in office. He ordered its criminal gangs to be designated as foreign terrorist organisations (FTOs),