The time has come for the international community to start exerting massive pressure on Iran over its nuclear program, British opposition leader David Cameron told Haaretz in an interview yesterday.

The Tory Party leader, who arrived in Israel for a three-day visit on Wednesday, came here mainly to learn, in an effort to better understand this tiny country that supplies so many headlines. And no matter how much you read or how many pictures you see, he said, it is not the same as seeing for yourself.

This is Cameron's first visit to Israel, but the man who the polls predict will win Britain's next election, scheduled to take place in about three years, already has several strong opinions. He does not rule out military action against Iran.

"I don't want to see military action," he said. "I don't think it is the right answer. But I don't think that in international affairs, you should take things off the table, rule things out. That is not the right approach. What the whole international community should be doing, and I discussed it today with your prime minister and the Likud leader, we should be putting the maximum amount of pressure on Iran to suspend uranium enrichment and to give up the desire for nuclear weapons."

In his blog, the 40-year-old Cameron acknowledged that if Iran is indeed trying to obtain nuclear weapons, its president's repeated calls for Israel's destruction could hardly be "reassuring" to Israelis. However, he evaded a question as to whether he would condemn Israel should it attack Iran.

Though Cameron's Tories and Prime Minister Tony Blair's Labour Party are bitter rivals, their disputes focus mainly on domestic issues, along with a few major foreign policy issues, such as Iraq. Britain's Foreign Office thus believes that bilateral relations with Israel would not change significantly if the Tories took power.

For instance, Cameron backed Blair's position on Hamas. "We want to see real movement toward the Quartet principles," he said, referring to international demands that Hamas recognize Israel, renounce violence and honor previous Israeli-Palestinian agreements. "We can't give our taxpayers' money directly to an organization that is supporting terrorism and is not making progress toward recognizing Israel and renouncing violence. I think it's very clear what Hamas has to do."

In contrast to his hard line on Iran and Hamas, Cameron was one of Israel's harshest critics during its war with Hezbollah last summer, charging that "elements of the Israeli response were disproportionate."

"A true friend of Israel always wants Israel to act with moral authority and to maintain its moral authority," he said. "You have moral authority, because you are a democracy, because you are a successful country, and we want you to maintain that moral authority, though it's incredibly difficult, because you are under that pressure that you are under. I don't think it's to be a true friend of Israel not being candid, being frank."

In the British media, Cameron is known as "Mr. Nice Guy." He admires Margaret Thatcher, pushes environmentalism, rides a bicycle to Parliament, advocates family values, and admits to having smoked marijuana. He has declined to answer questions about whether he ever used hard drugs.

He is considered anti-American in comparison to Blair, particularly after he chose the fifth anniversary of the September 11, 2001 terror attacks as his moment to launch a broadside against the British-American relationship under Blair. He reiterated his criticism to Haaretz, saying this relationship should be "solid but not slavish. The role of Britain is not just to be an echo to America, not just [to] repeat what America says, but to be a candid friend ... I think sometimes Prime Minister Blair got it wrong."

This morning, Cameron will meet with Palestinian Authority Chairman Mahmoud Abbas, and in the afternoon he heads back to Britain.

In Britain, many commentators compare Cameron to Blair 10 years ago. Cameron dislikes the comparison. "I find it incredibly annoying, with one exception," he said: "He did win rather a lot of general elections."