Iran's envoy to U.N. nuclear watchdog says his country will respond next week to a U.N.-drafted plan to ship much of its uranium to Russia for further enrichment.

Ali Asghar Soltanieh, Iran's permanent envoy to the International Atomic Energy Agency, told Iran's state Press TV on Friday that Iran is still studying the proposed deal.

The plan was drafted earlier this week in talks with the U.S., Russia and France in Vienna, Austria.

World powers saw it as a way to curb Iran's efforts to make nuclear arms.

Soltanieh's comments come hours after Iran's state TV quoted an unnamed source close to the Iranian nuclear negotiating team as saying Iran wants to buy nuclear fuel it needs for a research reactor, rather than accept the U.N. proposed plan.