The addition of visa overstays as a rationale could provide an opening for new legal challenges, migrant advocates say.

When Trump included Haiti in a list of countries on which he was imposing a near-total travel ban, some saw a culmination of a long campaign against the population.

A day after President Donald Trump proclaimed full or partial travel restrictions for Haiti, Cuba, Venezuela and 16 other countries, U.S. tourist-visa holders from the targeted nations lacked clarity about whether they will be allowed into the United States when the ban is in force Monday.