This post was last updated at 7:54 p.m. ET
The U.S. says enough progress has been made in talks with Iran on its nuclear program to warrant an extension of Tuesday's 6 p.m. ET deadline by a day.
"We've made enough progress in the last days to merit staying until Wednesday," spokeswoman Marie Harf said in a statement. "There are several difficult issues still remaining."
She said Secretary of State John Kerry, who was scheduled to leave the talks Tuesday, will remain until Wednesday.