Talks to revive Iran nuclear deal restart in Vienna

Diplomats from Iran and world powers reconvened in Vienna on Tuesday to seek a deal reviving Tehran's 2015 nuclear deal, with pressure mounting for results soon.

The United States has participated indirectly in the talks because it withdrew from the accord in 2018 under then-President Donald Trump. President Joe Biden has signaled that he wants to rejoin the deal. Under Trump, the U.S. reimposed heavy sanctions on Iran.  Tehran has responded by increasing the purity and amounts of uranium it enriches and stockpiles, in breach of the accord. The accord, formally known as the Joint Comprehensive Plan of Action, granted Iran sanctions relief in exchange for curbs on its nuclear program.