ISTANBUL — Talks between Iran and six world powers about the aims of its nuclear-enrichment program began on Saturday morning with a plenary session of all parties. European and American officials suggested that a serious commitment from Iran to negotiate may be enough to continue the talks at another round in late May, possibly in Baghdad, as Iran has suggested.

Iran agreed to resume these talks with six major world powers — the five permanent members of the U.N. Security Council, plus Germany — after more than a year without any negotiations, raising hopes in the West that Tehran might be ready to strike a deal over its nuclear program, which it denies has any military intent.


