David Miliband has played down suggestions he will herald a change in British foreign policy in his first interview since becoming foreign secretary.
In an interview with the Financial Times, Mr Miliband said Gordon Brown's government would not "retreat from the world".
The new prime minister will be a "robust defender of our national interest," the new foreign secretary said, after saying Britain would seek to become a "global hub".
Mr Miliband's appointment as foreign secretary had led some to speculate about a possible change of direction, pointing to his alleged scepticism over the Iraq war and criticisms of Israel's bombing of Lebanon last summer.
Speaking to the Financial Times, Mr Miliband played down such speculation and told people to focus on what he said on the record. He voted for the Iraq war, he reminded people, adding he would not take back that decision.
He also refused to rule out military actions against Iran, in an apparent hardening of opinion.
Two years ago, then foreign secretary Jack Straw said military action against Iran was inconceivable but Mr Miliband refused to reaffirm this position.
Instead he insisted the UK was working very hard to secure a non-military diplomatic solution.
"I don't think it does any good to speculate any wider than that. Our intent and our actions and our efforts are absolutely clear about the way we want to solve this," Mr Miliband said.
The foreign secretary adopted a firm line towards Iran, warning it had no right to spark a "nuclear arms race in the Middle East."
"Iran has every right to be a secure, rich country," he said. "It doesn't have the right to set off a nuclear arms race in the Middle East, and it doesn't have the right to undermine the stability of its neighbours."
Last week it was noted how Mr Miliband acknowledged Hamas' role in securing the release of BBC journalist Alan Johnston. Speaking to the Financial Times, he insisted the Palestinian group must recognise Israel's right to exist if it is to take part in the peace process.
He also said the UK would not change its policy on working with the US on a missile defence system.
On his first day as prime minister, Gordon Brown promised to push for a new direction, announcing "let the work of change begin".
The Conservatives have, however, attempted to portray him as the continuum of Tony Blair's government.