TEHRAN (AFP/Reuters) - Iran said on Monday it is considering plans to build two new uranium enrichment plants concealed inside mountains to avert air strikes, drawing condemnation from the United States. The announcement from Irans atomic chief Ali Akbar Salehi came soon after top US General David Petraeus warned that Washington would now pursue a pressure track against Iran to thwart its galloping nuclear programme. Inshallah (God willing), in the next Iranian year (starting in March) as ordered by the president we may start the construction of two new enrichment sites, Salehi told ISNA news agency. Salehi said the enrichment capacities of the new sites would be similar to the existing facility in the central city of Natanz, where a defiant Tehran is refining uranium despite three sets of UN sanctions. Salehi said the new plants will be equipped with new generation centrifuges and the facilities would be hidden in mountains so as to protect them from any attacks. Iran has earmarked potential sites for 10 new nuclear enrichment plants and construction of two of them could begin from March this year, a nuclear energy official said on Monday. We have earmarked close to 20 sites and have passed the report on those to the president, however, these sites are only potential, Ali Akbar Salehi, head of the Atomic Energy Organisation, was quoted as saying on news agency ISNA. We should begin the construction of two enrichment sites next year ... In the two new sites, we plan to use new centrifuges. The next Iranian year begins on March 21. The United States said the move showed Iran rejected diplomatic engagement with the international community. This is further evidence that Iran refuses to engage cooperatively and constructively with the IAEA, State Department spokesman Philip Crowley told reporters. Elsewhere on the diplomatic front, European nations at a meeting in Brussels on Monday appeared divided over boosting sanctions against Iran . Unhappily all the actions by the Iranian side for weeks confirm that we must move to (more) sanctions, French European Affairs Minister Pierre Lellouche said. But several of his EU counterparts said diplomacy had not run its course and insisted on the need for a UN Security Council decision. On Sunday, Petraeus said the United States, which along with its ally Israel has not ruled out military strikes against Irans nuclear sites, would increase pressure on Tehran. I think that no one at the end of this time can say that the United States and the rest of the world have not given Iran every opportunity to resolve the issues diplomatically, said Petraeus, head of US Central Command. That puts us in a solid foundation now to go on what is termed the pressure track. Thats the course on which we are embarked now, the general told NBC television. Israeli Prime Minister Benjamin Netanyahu on Monday insisted now was the time for new sanctions on Irans oil exports. Turkish Prime Minister Recep Tayyip Erdogan, meanwhile, warned in a newspaper interview that a pre-emptive Israeli strike on Irans nuclear facilities would be a disaster of unpredictable consequences. We have to find a solution through diplomatic means, he told the leading Spanish daily El Pais. We must not leave the negotiating table. Irans Deputy Foreign Minister Ali Ahani threatened Iran will hit back if attacked. Iran certainly will not start a war ... But if we are attacked, we will respond strongly, Ahani told Croatias Vecernji List daily. Meanwhile, Israeli Prime Minister Benjamin Netanyahu called on Monday for an immediate embargo on Irans energy sector, saying the UN Security Council should be sidestepped if it cannot agree on the move. Irans uranium enrichment in defiance of several rounds of Security Council sanctions has spurred world powers to consider tougher measures to halt what the West fears is a drive to produce nuclear weapons. Israel has endorsed the talks while hinting at preemptive military action should it deem diplomacy a dead end. If the world is serious about stopping Iran , then what it needs to do is not watered-down sanctions, moderate sanctions ... but effective, biting sanctions that curtail the import and export of oil into Iran , Netanyahu said in a speech. This is what is required now. It may not do the job, but nothing else will, and at least we will have known that its been tried. And if this cannot pass in the Security Council, then it should be done outside the Security Council, but immediately. Though it is the worlds fifth-largest oil exporter, Iran imports some 40pc of its gasoline from foreign refineries. Many Western diplomats believe that China, along with fellow veto-wielder Russia, would block any Security Council sanctions targeting Irans energy sector. Proposed sanctions for now focus on Iranian government assets like the Revolutionary Guard Corps. Netanyahu spokesman Mark Regev said Israel would prefer the Security Council to curb Iran but believed there was enough international support outside that forum for energy sanctions. If the United States, Europe and like-minded countries act in unison, they can succeed in sending the desired message and forcing the regime in Tehran to rethink its nuclear weapons programme, Regev said. Israels Haaretz daily reported in 2008 that Netanyahus predecessor, Ehud Olmert, proposed for the United States to enforce a naval blockage on Iran . Regev declined to discuss whether the current Israeli government had similar ideas. Netanyahu has in the past predicted energy sanctions would be enough to cripple Iran . He appeared to demur on Monday by raising the prospect that Iran-which announced plans to build two new enrichment plants-could weather even an oil embargo. Regev said the premier was speaking extemporaneously in his English address to diaspora Jewish leaders, and that there was no change to Israels strategic view on its arch-foe. Iran says its uranium enrichment is for energy or medical needs, but Tehrans anti-Israel rhetoric and support for Islamic guerrillas on the Jewish states borders, as well as concerns over an Israeli military strike, have stirred fears of conflict. Netanyahu made no reference to the possibility that Israel, which is assumed to have the Middle Easts only atomic arsenal, would try to attack Irans nuclear facilities. Some analysts believe this option is circumscribed by the long ranges, Iranian defences, and US reluctance to see another regional conflict.