By Fredrik Dahl
VIENNA (Reuters) - Russia and China backed four Western powers on Wednesday to step up diplomatic pressure on Iran to allay concerns that it is developing atomic bombs capability, a day after Israel ramped up threats to attack the Islamic state.
The United States, France, Germany and Britain as well as Russia and China agreed a draft resolution at the U.N. nuclear agency to rebuke Iran over its expanded uranium enrichment program while making clear their desire to find a peaceful resolution to the dispute which risks a new Middle East war.
Russia and China, critical of unilateral Western sanctions on Iran's oil exports, were initially reluctant to submit a resolution on Iran to the 35-nation board of the International Atomic Energy Agency (IAEA), diplomats said.
In contrast to the West's and the IAEA's assessments, Russian Deputy Foreign Minister Sergei Ryabkov last week said there were no indications of a military nuclear program in Iran.
The IAEA board is set to vote on Thursday on the text put forward by the six states, involved in a stalled diplomatic push to convince Iran to curb its nuclear activity.
Designed to show big power unity on the matter despite different views on Iran's nuclear program, it seemed unlikely to have any immediate impact on Tehran, which has pressed ahead with its atomic activities despite harsh economic sanctions.
Backing by the six powers means approval by the board is guaranteed, but Western diplomats are keen to ensure near unanimous support in a bid to increase isolation of Tehran, which they suspect wants to develop a nuclear weapons capability. Iran says its work is peaceful.
Escalating tension on how to deal with Iran, Israeli Prime Minister Benjamin Netanyahu said on Tuesday that if world powers refused to set a red line for Tehran's nuclear program, they could not demand that Israel hold its fire.
Last November, only Cuba and Ecuador voted against a board resolution censuring Iran after a report by the IAEA, a Vienna-based U.N. nuclear agency, gave details of suspected atom bomb research by Tehran, some of which may continue.
IRANIAN COOPERATION "URGENT"
Wednesday's draft text expressed "serious concern" about Iran's defiance of U.N. demands to suspend nuclear work which can have both civilian and military purposes, and urged it to cooperate with IAEA inspectors and grant them access to sites.
It voiced particular concern about Fordow, an Iranian enrichment site deep underground where an IAEA report in late August said the Islamic Republic had doubled its capacity over the last three months.
Iran says it wants to produce electricity and not bombs. Refined uranium can be used to fuel nuclear power plants. If enriched to a high degree, it can provide the explosive core for a nuclear warhead.
Israel, believed to be the Middle East's only nuclear-armed state, sees the risk of Iran developing an atom bomb as a threat to its existence and has stepped up hints of military action.
Washington says there is still time for diplomacy and sanctions to make Tehran change course.
In their proposed resolution, the six powers voiced continued "support for a peaceful resolution of the international community's concerns".
They said Iran should immediately agree a framework accord with the U.N. nuclear watchdog to clarify questions over possible military dimensions to its nuclear program.
An IAEA investigation into suspected nuclear weapons development work in Iran has made little progress over the last four years, with the West accusing Tehran of stonewalling.
Iranian cooperation with the IAEA "is essential and urgent in order to restore international confidence in the exclusively peaceful nature of Iran's nuclear program", the powers said.
(Editing by Louise Ireland)