An Iranian negotiator returned to Pakistan on Sunday, despite the United States abruptly calling off a trip there by its two top negotiators.

Cease-fires in Lebanon and Iran are on shaky ground, with military attacks flaring and direct talks between Washington and Tehran to end their war stalled.

The British royals are set to arrive on Monday for a visit hosted by President Trump, with a garden party, an address to Congress and a banquet on the schedule.

The two Americans were killed on Sunday when their vehicle crashed while returning from an antidrug operation led by Mexico’s armed forces in the state of Chihuahua.

The last-minute scuttling of the trip to Pakistan was the latest sign of how far apart the two sides are on reaching a deal to end the Iran war.

In an unsanctioned mission, the Foreign Service officer helped evacuate about 200 South Vietnamese citizens from Saigon days before the city fell in 1975.

President Trump withdrew from the Obama-era nuclear accord in 2018, saying it was the worst deal ever. But Iran responded with an enrichment spree that haunts the negotiations to this day.

President Trump has outsourced much of his diplomacy to others, while Mr. Rubio focuses on his second job as national security adviser.

Iran’s foreign minister has already arrived in the country, state media reported. He was believed to be carrying a written response to a U.S. proposal to end the war.

Pressure from Washington helped drive a disputed deal forward, triggering resignations and raising questions about sovereignty.

The U.S.-mediated cease-fire halted an all-out war between Israel and Hezbollah, but their intensifying attacks on each other could put the truce at risk.

An internal Pentagon email, reported by the Reuters news agency, suggested Washington was reviewing options to penalize the two nations for insufficiently supporting the war in Iran.