India, April 21 -- The US Navy's forcible seizure of an Iranian-flagged cargo ship has thrown doubt on President Donald Trump's announcement that US negotiators would travel to Pakistan on Monday for another round of talks with Iran.

Trump's announcement Sunday had raised hopes of extending a fragile ceasefire set to expire by Wednesday, but then US Marines boarded the cargo ship that tried to circumvent a naval blockade near the Strait of Hormuz. Iran's joint military command said Tehran would respond soon to what it called an act of piracy, and Iran's Foreign Ministry spokesperson Esmail Baghaei on Monday said Tehran did not have plans yet to attend any talks with the United States.

The escalating standoff threatened to deepen the ene...