Amid heightened tensions in the Persian Gulf, Britain on Sunday said it would not be "wise" for Israel to launch pre-emptive military strikes on Iran's atomic installations as it would have "enormous downsides."
Foreign Secretary William Hague said that Britain has urged Israel not to strike. "We support a twin-track strategy of sanctions and pressure and negotiations on the other hand.
"All options must remain on the table" but a military attack would have "enormous downsides", he told the Daily Telegraph.
Separately, Hague told the BBC that the United Kingdom had not been shown any plans by Israel for an attack on Iran and had not been asked to be involved in any such attack.
"I don't think the wise thing at this moment is for Israel to launch a military attack on Iran," he said.
"I think Israel, like everybody else in the world, should be giving a real chance to the approach that we have adopted, of very serious economic sanctions and diplomatic pressure, and the readiness to negotiate with Iran. And that's what we now have to make a success of"
He said that the UK was 100 per cent focused on using diplomacy and economically targeted sanctions "bringing Iran back to the table".
Tensions over Iran's nuclear programme are running high.
Israel, the US, Britain and others suspect that Iran is using the programme as cover for producing of atomic weapons. Some observers fear that Israel may be planning a strike against Iran, the world's third largest oil exporter.
In response, Iran has threatened to withhold its own oil deliveries and to block the Strait of Hormuz, a strategic waterway along its coastline through which one-fifth of the world's oil flows.
Hague's comments also come amid heightened tensions in the Middle East, with Israel accusing Iran of masterminding attacks on its embassies in India, Thailand and Georgia. Iran denies the allegations.
Hague also said other nations in the region would want to develop nuclear weapons if Iran did.
"If (the Iranians) obtain nuclear weapons capability, then I think other nations across the Middle East will want to develop nuclear weapons. And so, the most serious round of nuclear proliferation since nuclear weapons were invented would have begun with all the destabilising effects in the Middle East," Hague told the Daily Telegraph.
Without "the safety mechanisms" of the US-USSR rivalry, Hague said it would be "a disaster in world affairs".
Last week, Iran staged an elaborate ceremony to unveil new developments in its nuclear programme. Iran said it had used domestically-made nuclear fuel in a reactor for the first time.
Talks between Iran and six world powers - the United States, UK, France, Germany, Russia and China - on Tehran's nuclear programme collapsed a year ago.
In recent months, Western countries have stepped up pressure on Iran over the nuclear issue, with the EU and US both introducing wide-ranging sanctions on Tehran. Iran insists its nuclear programme is for energy purposes.
Meanwhile, Iranian warships have entered the Mediterranean Sea for only the second time since the 1979 revolution.
The destroyer Shahid Qandi and its supply vessel Kharg have passed through the Suez Canal but their destination remains unclear, media reports said.