WASHINGTON - President Barack Obama headed for the Middle East on Tuesday hoping to start mending U.S. ties to the Islamic world in a speech that aides say will reach out to Muslims but deal with tough issues like the peace process and violent extremism.

Obama will use his address in Cairo this week to try to repair some of the damage to America's image caused by the Iraq war, U.S. treatment of military detainees and the lack of progress in Middle East peace talks.

I am confident that we're in a moment where in Islamic countries, I think there's a recognition that the path of extremism is not actually gonna deliver a better life for people, Obama told NBC News shortly before departing.

I think there's a recognition that simply being anti-American is not gonna solve their problems. The steps we're taking now to leave Iraq takes that issue and diffuses it a little bit, he said.

Obama spokesman Robert Gibbs told reporters at the White House earlier the purpose of the speech was about resetting our relations with the Muslim world.

The success of the U.S. leader's diplomatic initiatives in the region -- like advancing the Israeli-Palestinian peace process and halting Iran's nuclear program -- may depend on how well Obama, whose father was a Muslim and who lived in Indonesia as a boy, is able to improve U.S.-Islamic ties.

Obama cautioned against expecting too much from the speech, which he said was just the first step in opening a broader dialogue with the Muslim world.

After all, one speech is not gonna transform very real policy differences and some very difficult issues surrounding the Middle East and the relationship between Islam and the west, Obama said.

The first stop on the president's four-day visit to the Middle East and Europe is Saudi Arabia, where he will hold talks with King Abdullah on issues like the Mideast peace process, Iran's nuclear program and energy prices.

Washington and Riyadh differ over oil prices. Obama has spent heavily trying to lift the U.S. economy out of a major recession and has expressed concern about oil price spikes, which could hurt any recovery.

Saudi Arabia has been calling for stable prices, but at $75-$80 a barrel, versus the current price of $68, said David Ottaway, a Mideast scholar at the nonpartisan Wilson Center.

On oil prices, there are, I think, significant and sharp differences in the two positions, he said.

The Saudis would like to see greater pressure on Iran over its nuclear enrichment program, which the West fears is aimed at making atomic weapons but Tehran says is for nuclear power. The Saudis also are frustrated at the lack of progress toward a settlement of the Israeli-Palestinian conflict.

'FED UP WITH TALK'

Obama travels on Thursday to Cairo, where he will fulfill a campaign promise to deliver a speech to the Islamic world from a major Muslim capital early in his presidency.

The speech will outline his personal commitment to engagement, based upon mutual interests and mutual respect, Gibbs said.

Though his planned address has been well-received by mainstream Muslims, Ayman al-Zawahri, second-in-command to the Islamist al Qaeda network, urged Egyptians not to be seduced by Obama's polished words.

Stand united in the face of this criminal, Zawahri, an Egyptian, said in an audio recording posted on an al Qaeda-linked Islamist website. (Obama's) bloody messages have been received and are still being received and they will not be concealed by public relations campaigns or theatrical visits.

While talking about ways to improve U.S.-Muslim relations, Obama also will discuss difficult issues like extremist violence and the Israeli-Palestinian conflict, aides said.

He doesn't hesitate to take on the tough issues in his speech, said Deputy National Security Adviser Mark Lippert.

Aaron David Miller, a Wilson Center public policy analyst, said Obama's speech would be closely watched in the region to see whether it would break new ground on the Arab-Israeli conflict or would say anything about authoritarianism, human rights and good governance in the Muslim world.

If he doesn't do either of those two things, this is going to be a dog bites man speech. It's not going to be a man bites dog speech, which is what ... the Arab and Muslim world is expecting: something new, something different and something real, he said.

After Cairo, the U.S. leader will travel to Europe for visits steeped in World War Two symbolism -- the Nazi Buchenwald concentration camp in Germany and the beaches of Normandy in France to mark the 65th anniversary of D-Day.

He will meet German Chancellor Angela Merkel and French President Nicolas Sarkozy during his European trip as part of his effort to improve transatlantic ties.

(Editing by Eric Walsh and Jackie Frank)

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