* Deputy nuclear negotiator says Tehran awaits word from EU
* Says conversion of enriched uranium to oxide is continuing
* Ashton's office says has arranged to call Iran's Jalili (Adds quotes, byline, EU reaction)
By Stephanie Nebehay
GENEVA, April 25 (Reuters) - Iran is ready to resume talks with world powers on its disputed nuclear programme and awaits word from the European Union on timing and details, Iran's deputy nuclear negotiator said on Thursday.
Ali Bagheri, in an interview with Reuters in Geneva, said Iran needed 20 percent-enriched uranium for its Tehran research reactor and four others being built, and was continuing to convert some of its stockpile into reactor fuel.
"We are waiting for Lady Ashton to call Dr. Jalili, and Dr. Jalili is obviously ready to take the call," Bagheri said.
EU foreign policy chief Catherine Ashton oversees diplomatic contacts with Iran on behalf of the the United States, Russia, China, France, Britain and Germany. Saeed Jalili is Iran's chief negotiator.
"We are waiting to see whether Lady Ashton's response is going to cover the time and venue of another round of negotiations, or will she limit her response to just discussing the substantive side of things," Bagheri said.
In Brussels, a spokesman for Ashton said she had consulted with foreign ministers on how to move forward the process. "Arrangements for a phone call with Dr. Jalili have already been made in order to discuss next steps," Michael Mann said.
The six powers and Iran failed in talks in the Kazakh capital Almaty this month to end the deadlock in a decade-old dispute over Tehran's nuclear programme, prolonging a standoff that could yet spiral into a new Middle East war.
At those talks, the six asked Iran to suspend its most sensitive uranium-enrichment work in return for modest relief from international sanctions, an offer Tehran did not accept.
Iran's presidential election is set for June 14, leading to speculation on whether the next round of talks will take place before the poll. "We are ready to continue with the talks ... We have no limits as far as time is concerned," Bagheri said.
Israel, which has long hinted at possible air strikes to deny its arch-foe any means to make a nuclear bomb, suggested this week it would be patient before taking any military action.
Iran says its nuclear work is entirely peaceful and that it is only refining uranium to power a planned network of nuclear energy plants and for medical purposes. Critics accuse it of covertly seeking the means to produce nuclear weapons.
"NO CAUSE FOR CONCERN"
Bagheri, referring to the U.N. nuclear watchdog, the International Atomic Energy Agency (IAEA), said: "I need to point out the Islamic Republic of Iran uranium enrichment activities to the level of 20 percent is under strict agency monitoring. Obviously activities that are being monitored by the agency are no cause for concern."
An IAEA report in February said Iran had in December resumed converting to oxide powder some of the uranium it has enriched to 20 percent fissile concentration, for the production of reactor fuel.
That helped restrain the growth of Iran's higher-grade uranium stockpile, a development that could buy more time for diplomacy.
In a potentially encouraging sign for the powers, Bagheri said on Thursday this conversion was continuing.
"We produce 20 percent uranium to provide fuel for Tehran's research reactor, also four other reactors in four different parts of Iran which are under construction. With this in mind, plans have been drawn up to convert 20 percent uranium to 20 percent oxide," Bagheri said.
"This is very much going according to plan. This activity is ongoing," he added.
The IAEA said on Tuesday it would hold a meeting with Iran on May 15 aimed at enabling its inspectors to resume a stalled investigation into suspected nuclear bomb research, the 10th round of talks since early 2012.
Bagheri said Iran was already cooperating fully with the IAEA but was willing to discuss requests "which go beyond our obligations" under the nuclear Non-Proliferation Treaty.
"We are very much hoping in this round of talks between my country and the agency, we no longer have such meddling and sabotaging of talks," he said.
"Experience tells us that usually certain Western parties, including the U.S., whenever we are close to striking a bargain, reaching an agreement, they interfere."
The IAEA-Iran talks are separate from, but have an important bearing on, the negotiations between Tehran and world powers. Iran's refusal to curb sensitive nuclear activity with both civilian and military applications and its lack of openness with IAEA inspectors have drawn U.N. and Western sanctions.
"Once we reach an agreement with the agency, we also expect the (six powers), because of such cooperation with the agency which goes well beyond our obligations, to lift a number of sanctions. Unilateral sanctions which are illegal," Bagheri said. (Reporting by Stephanie Nebehay; additional reporting by Fredrik Dahl in Vienna and Justyna Pawlak in Brussels; editing by Andrew Roche)