The UK foreign secretary says military action is still inconceivable against Iran and he hopes diplomacy can solve deadlock over its nuclear programme.
Straw says an attack on Iran would not solve the problem
US President George W Bush has refused to rule out military strikes against Iran, which Washington accuses of wanting to develop nuclear weapons.
"It is not on the agenda, I happen to think that it is inconceivable," Jack Straw told BBC radio.
Iran insists its nuclear activities are purely peaceful, to produce fuel.
Last week the United Nations nuclear watchdog passed a resolution that took Iran a step closer to sanctions if it did not ease suspicions about its intentions.
The International Atomic Energy Agency resolution orders Iran to suspend enrichment activities, stop building its heavy water nuclear reactor and open up to inspections.
Mr Straw said that European negotiators - with US backing - had "left the door open for further diplomatic action with Iran and I hope that they take this opportunity".
Iran has rejected the IAEA vote, with its foreign minister calling it "political, illegal and illogical".
Tehran is threatening to cease application of the Nuclear Non-Proliferation Treaty's additional protocol, which allows snap inspections of nuclear sites, if the IAEA reports Tehran to the Security Council.
A bill has been presented to the Iranian parliament aimed at suspending implementation of the additional protocol until Iran completes the nuclear fuel cycle.
So far, parliament only voted to consider the bill as an urgent piece of legislation and now it goes to several committees.
The BBC's Frances Harrison in Tehran says it is not clear how long the process will take, but if put to a vote in parliament it is certain to be passed.
Iran has signed - but not ratified - the additional protocol.
Tehran recently restarted work on the early stages of uranium enrichment.
Such work had been suspended since November 2004 while talks were held with the UK, France and Germany about its long-term nuclear plans.
Iran hid an uranium enrichment programme for 18 years until its activities were exposed in 2002.