Dhaka, Dec. 11 -- Iran's troubled currency fell to a new low against the US dollar on Saturday amid continued unrest and the country's increasing isolation in the face of Western criticism of its security crackdown and ties to Russia.

The dollar was selling for as much as 370,200 rials on the unofficial market on Saturday, up from 367,300 on Friday, according to the foreign exchange site Bonbast.com.

The rial has lost 13.8% of its value since nationwide protests erupted after the death in police custody of a 22-year-old Kurdish Iranian woman, Mahsa Amini, on Sept 16, reports Reuters.

The unrest poses one of the biggest challenges to theocratic rule in Iran since the 1979 Islamic Revolution.

The economic Ecoiran website said traders sa...