Israel gave serious thought earlier this year to a military strike on Iran's nuclear sites but was told by US President George W. Bush he would not support it, Britain's Guardian newspaper reported Friday. Quoting what it called senior diplomatic sources who work for a European head of government, the Guardian said Bush told Israel he did not expect to revise that view for the rest of his presidency. Mark Regev, spokesman for Israeli Prime Minister Ehud Olmert, said Israel preferred a diplomatic solution to the dispute over Iran's nuclear program. But Regev added: “All options must remain on the table.” The Guardian said Olmert, who submitted his resignation this week but remains caretaker premier, used the occasion of Bush's trip to Israel for the 60th anniversary of the state's founding to raise the issue in a one-on-one meeting on May 14. “He took (the refusal of a US green light) as where they were at the moment, and that the US position was unlikely to change as long as Bush was in office,” said one source. Bush leaves office in January. Regev said Olmert raises “the need to prevent Iran from obtaining nuclear weapons” in every meeting he has with foreign leaders. But Regev denied the specific exchange cited in the Guardian. “The words attributed to the prime minister by the Guardian's anonymous source were not spoken in any working meeting between the prime minister and foreign visitors,” the spokesman said. Israel, widely thought to have the Middle East's only atomic arsenal, believes Iran could have a nuclear bomb by 2010 and says an Iranian nuclear weapon would threaten the existence of the Jewish state. Iran, the world's fourth-largest oil exporter, denies seeking nuclear arms and says it is enriching uranium only for use in generating power to meet the demands of its economy. The Guardian said the European head of government met Olmert some time after Bush's visit and that although their talks were so sensitive that no note-takers attended he subsequently divulged the contents to his officials.