White House: Iran's nuclear proposal "very useful"

Iranian Foreign Minister Mohammad Javad Zarif attends a press conference closing two days of closed-door nuclear talks on October 16, 2013 in Geneva. Talks between world powers and Iran on its controversial nuclear programme could herald a shift in Tehran's ties, Foreign Minister Mohammad Javad Zarif said. FABRICE COFFRINI/AFP/Getty Images

WASHINGTON The White House says an Iranian proposal addressing its nuclear program is useful and contains a, quote, "level of seriousness and substance that we have not seen before."

White House spokesman Jay Carney says not to expect a prompt breakthrough in the high-level nuclear talks between Iran and six world powers.

Still, the talks ended on a positive note Wednesday. The European Union's top diplomat called them, quote, "very important."

A new meeting among the parties is scheduled for Nov. 7-8 in Geneva.

Carney says, quote: "We found the Iranian presentation very useful."

He added that the deal must prove to the international community that Iran's nuclear program is exclusively for peaceful purposes.

Reporting from Geneva, CBS News correspondent Elizabeth Palmer said the talks got very serious very fast. An administration official told CBS News they had never had such candid, intense and straightforward talks with the Iranians. As Palmer reported, a lot of that has to do with Iran's lead negotiator who is also the Iran's foreign minister, Javad Zarif. He conducted the talks in English and it really helped things along. None of the details have leaked -- negotiators say it's top secret and has to stay that way because these talks have so much riding on them. They broke up Wednesday, saying there is lots to keep talking about.