WASHINGTON (CNN) -- Sen. John McCain Monday called for tougher worldwide pressure on Iran and painted his potential rival Sen. Barack Obama as naive about the Middle East.

Speaking to a pro-Israeli group, Sen. John McCain calls for targeted sanctions against Iran's leaders.

The presumptive Republican presidential nominee called for "targeted sanctions that will impose a heavy cost on the regime's leaders," such as limiting Iran's ability to import gasoline, denying travel visas to its leaders, freezing their assets and imposing financial sanctions on its central bank.

McCain was speaking at the annual conference of the American Israel Public Affairs Committee, the influential pro-Israel lobbying organization.

In a clear sign McCain has begun his general election campaign, the speech was peppered with attacks on Obama, the Illinois senator who is the front-runner for the Democratic presidential nomination. Watch McCain slam Obama on Iraq »

McCain made his target unmistakable, mentioning Obama by name in two of his three criticisms about Middle East policy matters.

The Obama campaign fired back immediately, sending reporters a lengthy e-mail rebutting McCain's points one by one as McCain began speaking.

McCain took Obama to task for the latter's stated willingness to meet with the leaders of countries like Iran, which the Arizona Republican described as the greatest threat facing Israel.

"We hear talk of a meeting with the Iranian leadership offered up as if it were some sudden inspiration, a bold new idea that somehow nobody has ever thought of before," McCain said without naming Obama.

"Yet it's hard to see what such a summit with [Iranian] President [Mahmoud] Ahmadinejad would actually gain, except an earful of anti-Semitic rants, and a worldwide audience for a man who denies one Holocaust and talks before frenzied crowds about starting another.

He blasted Obama for voting against a measure to label Iran's Revolutionary Guard a terrorist organization, noting that three-quarters of the Senate supported the resolution.

"He opposed this resolution because its support for countering Iranian influence in Iraq was, he said, a 'wrong message not only to the world, but also to the region.' But here, too, he is mistaken. Holding Iran's influence in check, and holding a terrorist organization accountable, sends exactly the right message -- to Iran, to the region and to the world."

McCain also jabbed Obama over Iraq, saying America's counterinsurgency strategy there was succeeding.

"It's worth recalling that America's progress in Iraq is the direct result of the new strategy that Senator Obama opposed. It was the strategy he predicted would fail, when he voted cut off funds for our forces in Iraq," McCain said.

"He now says he intends to withdraw combat troops from Iraq -- one to two brigades per month until they are all removed. ... This course would surely result in a catastrophe."

The Obama campaign, in response, sought to tie McCain to President Bush, who it said had failed to contain Iranian influence over the past seven years. Watch Obama say McCain was running for 'Bush's third term' »

"Confronted with that reality, John McCain promises four more years of the same policies that have strengthened Iran, making the United States and Israel less safe," Hari Sevugan, an Obama campaign spokesman, said.

The Obama campaign accused McCain of misrepresenting the Democrat's positions and offering only empty rhetoric himself.

McCain "promises to continue a war in Iraq that has emboldened Iran and strengthened its hand," Obama's campaign wrote. "He promises sanctions that the Bush administration has been unable to persuade the Security Council to deliver.

"He promises a divestment campaign, even though he refused to sign on to Barack Obama's bipartisan divestment bill, refused to get his colleagues to lift an anonymous hold on the bill, and willfully ignores the fact that trade and investment between Iran and Iraq continue to expand. He stubbornly refuses to engage in aggressive diplomacy, ruling it out unconditionally as a tool of American power."

The campaign said Obama is in favor of divestment from Iran and of labeling the Revolutionary Guard a terrorist organization. It said Republicans had blocked Obama's own divestment bill, and that the senator had voted against a bill about the Revolutionary Guard because it contained other provisions about Iraq to which he objected.

It also said Obama would base decisions about withdrawing U.S. combat troops from Iraq on facts on the ground. Obama is due to address AIPAC on Wednesday.

The speech -- one of a series of addresses laying out policies McCain would pursue as president -- included a nod to the United Nations, but the candidate made clear he would press ahead with or without the world body's support.

"Essential to this strategy is the U.N. Security Council, which should impose progressively tougher political and economic sanctions. Should the Security Council continue to delay in this responsibility, the United States must lead like-minded countries in imposing multilateral sanctions outside the U.N. framework."

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