Western powers said on Tuesday Iran’s continued stockpiling of enriched uranium devalued its deal to give up some of its potential nuclear bomb material, signalling Tehran would not evade more sanctions this way.

Under the deal agreed with Turkey and Brazil last week, Iran would send 1.2 tonnes of its low-enriched uranium (LEU) to Turkey for safekeeping until Tehran received specially processed fuel for its medical isotope reactor around a year later.

But Western critics said the accord, echoing one brokered by the U.N. nuclear watchdog in October involving the same amount of LEU, would still leave Iran with enough material for one bomb, if enriched to high purity, since it is estimated to have almost doubled its LEU reserve with daily enrichment since then.

The United States, France and Russia — parties to the original deal in principle — saw it as a way to divest Iran of enough LEU to prevent covert “weaponisation”, while giving Iran the means to maintain care for some 850,000 cancer patients.

But U.S. Secretary of State Hillary Clinton condemned Iran’s gesture, six months after it backed away from the accord, as a “transparent ploy to avoid (U.N.) Security Council action” to pass a fourth Iran sanctions resolution now on the table.

Clinton, speaking after talks with Chinese leaders in Beijing, and French officials said Iran’s launch of higher-level enrichment in February seemed to eclipse any fuel swap deal.

“We discussed at some length (with the Chinese) the shortcomings of the recent proposal put forward by Iran … There are a number of deficiencies with it that do not answer the concerns of the international community,” Clinton said.

British Prime Minister David Cameron said that even if Iran followed through on the deal, it would still retain half of its LEU reserve — sufficient for one nuclear warhead.

HARSHER SANCTIONS STAY ON TABLE

“I believe it is time to ratchet up that pressure, and the timetable is short. This government has a clear objective to ensure stronger U.N. and EU sanctions against Iran,” Cameron said during parliamentary debate in London on Tuesday.

France’s Foreign Ministry spokesman said Iran’s extended uranium enrichment activities were problematic for its proposal, conveyed on Monday to the International Atomic Energy Agency (IAEA) which passed it on to Paris, Washington and Moscow.

Iran’s simultaneous reiteration that it would not rein in enrichment in any way, defying a series of resolutions by the IAEA and Security Council, “is being taken into account and it’s part of the problem,” spokesman Bernard Valero said.

“At the time (of the October deal) we were talking about 1,200 kilogrammes and now the stockpile must be around 2-2,400 kilogrammes,” Valero said. “There’s a bit of a difference between the two and that is also part of the problem.”

Iran insists its uranium enrichment programme is for solely peaceful purposes of electricity generation and medical care. But it has a history of hiding sensitive nuclear activity from the IAEA and continues to restrict U.N. inspections.

In Moscow on Tuesday, Iran’s ambassador to Russia was quoted by Interfax news agency as warning that Tehran would reconsider the new deal if further sanctions were imposed. Iran has called for renewed talks with the big powers on details of the pact.

“If there are new sanctions, it will become obvious to the Iranian public that the ’5 + 1′ group is hiding evil intentions and pursuing political objectives. This would force us to revise the Tehran accords,” Mahmoud Reza Sadjadi was quoted as saying.

“We believe that by this (deal) Iran has demonstrated its goodwill,” Sadjadi said. “After all that lobbying by Brazil, Turkey and other countries, we believe that it makes no sense to talk about new sanctions.”

Prime Minister Benjamin Netanyahu of Israel, Iran’s arch regional enemy, dismissed Tehran’s nuclear offer as “empty”.

“(That’s because Iran)…continues to enrich uranium it has at a high level, and reserves the right, according to this proposal, to take (what) it’s meant to transfer to Turkey back to Iran at any time,” Netanyahu told the Israeli parliament.

The draft sanctions resolution agreed by six world powers — the United States, Britain, France, Germany, Russia and France — last week is being discussed with other Security Council members for what Washington hopes will be approval next month.

The extended sanctions provisions would target Iranian banks and call for high-sea inspections of vessels suspected of carrying cargo related to Iran’s nuclear or missile programmes.

(Additional reporting by Tim Castle in London, Vicky Buffery in Paris, Ari Rabinowitch in Jerusalem, Dmitry Solovyov in Moscow; Writing by Mark Heinrich; Editing by Michael Roddy)