However failure would aggravate fears of a wider conflagration across a region that exports much of the world's oil
Tehran has cautioned neighbouring countries that have US bases that they would face "severe consequences" if they were involved in any US military attack on the OPEC member
Iranian Foreign Minister Abbas Araqchi told Iranian TV
Quote
"There is a chance for initial understanding on further negotiations if the other party (US) enters the talks with an equal stance"
an Iranian official told Reuters that Iran's Supreme Leader Ayatollah Ali Khamenei, who has the final say on key state matters, has given Araqchi
Quote
"full authority" for the talks
Iran has ruled out negotiating its defence capabilities such as its ballistic missile programme
Western nations say Iran's enrichment of uranium, a nuclear fuel source, has gone far beyond the requirements of a civilian energy programme and has produced stocks at a level of fissile purity close to those required in warheads
Trump, who has restored a "maximum pressure" campaign on Tehran since February, ditched a 2015 nuclear pact between Iran and six world powers, including Russia and China, in 2018 during his first term and reimposed crippling sanctions on the Islamic Republic
Since then Iran's nuclear programme has leaped forward including by enriching uranium to 60% fissile purity, a technical step from the levels needed for a bomb
Reporting by Parisa Hafezi in Dubai; Additional reporting by Jeff Mason aboard Air Force One; Writing by Parisa Hafezi and David Brunnstrom; Editing by Susan Fenton, Frances Kerry, Mark Heinrich, Don Durfee, Diane Craft and Marguerita Choy
