Dhaka, March 14 -- A letter from U.S. President Donald Trump to Iran's Supreme Leader Ayatollah Ali Khamenei has arrived in Tehran, aiming to revive talks over Iran's advancing nuclear program.

Though the contents of the letter remain undisclosed, its arrival coincides with Trump imposing new sanctions as part of his "maximum pressure" strategy. While keeping military action on the table, he has also expressed confidence in the possibility of a new agreement.

Khamenei, 85, has publicly dismissed Trump, but Iranian officials have sent mixed signals on the prospect of negotiations.

Why Did Trump Send the Letter?

Trump confirmed in a televised interview on March 6 that he had written to Khamenei, stating, "I hope you're going to negotiat...