WASHINGTON (AP) — Ending a second day of tense negotiations, U.S. and Mexican officials failed Thursday to reach a deal to avert import tariffs that President Donald Trump is threatening to impose as he tries to strong-arm Mexico into stemming the flow of Central American migrants across America's southern border.

Vice President Mike Pence, monitoring the talks from his travels in Pennsylvania, said the U.S. was "encouraged" by Mexico's latest proposals but, so far, tariffs still were set to take effect Monday.

Pence added that it would be "for the president to decide" whether Mexico was doing...