ISLAMABAD, April 27 -- Iran's foreign minister returned to Islamabad on Sunday, ping-ponging from capital to capital as mediators hoped to keep peace talks between Tehran and the United States alive.

Abbas Araghchi visited Oman's Muscat on Saturday after leaving Pakistan, and is set to meet Russian President Vladimir Putin in Moscow on Monday, but there remained no indication that direct US-Iranian talks would resume.

On Saturday, US President Donald Trump scotched a planned trip to Islamabad by his negotiators Steve Witkoff and Jared Kushner.

But in a sign that indirect efforts were ongoing, the Fars news agency reported that Iran had transmitted "written messages" to the Americans via Pakistan that were "about some of the red lines o...