US does about-turn and sends envoy to Iran talks

(Adds more details, quotes)

By Sue Pleming

WASHINGTON, July 15 (Reuters) - In a shift in policy, the United States will send an envoy to talks with Iran's nuclear negotiator this weekend along with other world powers dealing with Tehran, a senior U.S. official said on Tuesday.

The official said U.S. Under Secretary of State William Burns would for the first time join the EU's Javier Solana and envoys from China, Russia, France, Britain and Germany in a meeting on Saturday with Iranian negotiator Saeed Jalili in Geneva.

The six would discuss Iran's response to an offer made by world powers last month to give up sensitive nuclear work the West believes is aimed at building an atomic bomb and which Tehran says is for peaceful power generating purposes.

The United States had said previously it would not be involved in any pre-negotiations with Tehran unless it gave up uranium enrichment and the meeting is a change to that policy.

The U.S. official made clear the ground rules for the meeting were that Burns would not act as a negotiator but rather put forward the White House position that Iran must give up enrichment for any real talks to start.

"Bill Burns will reiterate our terms for negotiation remain the same," said the official, who asked not to be named according to department rules.

"This will be a one-time participation designed to show unity (among major powers) and the message will be very clear," the official told Reuters.

The U.S. presence at the meeting with Solana did not indicate a restoration of full-blown diplomatic ties with Iran, he said.

Despite having no diplomatic relations with Iran, the United States has held several rounds of talks over the past year with Iran over what it sees as Tehran's meddling with Iraq.

Iran, the world's fourth largest oil producer, denies it wants to build nuclear weapons and says its nuclear program is designed to produce electricity to increase its output of oil and natural gas. (Reporting by Sue Pleming, editing by John O'Callaghan and Jackie Frank)