British Prime Minister Tony Blair said Wednesday that Iran remains the largest obstacle to peace in the Middle East and moderate forces around the globe must organize to fight extremism.

Speaking in Dubai at the end of a Middle East tour, Blair said the Iranian government of President Mahmoud Ahmadinejad is the main enemy of moderation in the region.

"There is a monumental struggle going on worldwide between those who believe in democracy and moderation, and forces of reaction and extremism," Blair said.

"We have to wake up. These forces of extremism — based on a warped and wrongheaded misinterpretation of Islam — aren't fighting a conventional war.… We must therefore mobilize our alliance of moderation in the region and outside of it to defeat the extremists."

Blair accused Iran of supporting insurgent forces in Iraq, undermining the Lebanese government through its support of the militant group Hezbollah and blocking efforts to foster peace between Israel and the Palestinian territories by sponsoring the militant group Hamas.

"And yet a huge part of world opinion is frankly almost indifferent," he said.

"It would be bizarre if it weren't deadly serious. We must recognize the strategic challenge the government of Iran poses."

Blair rejected suggestions that U.S. and British foreign policies in the Middle East have helped to create a climate where extremism can thrive.

One of his last foreign trips as prime minister, the Mideast tour took Blair to Turkey, Egypt, Iraq, Israel, the Palestinian territories and the United Arab Emirates.

He pledged support for Turkey's bid to join the European Union, Egypt's efforts to mediate peace between Israel and the Palestinians and the UAE's economic openness in Dubai, which he called a model for the Arab world.
  
"For good or ill," Blair said, what happens in the Middle East would have an effect around the world.

Blair has said he will step down by the middle of next year.

With files from the Associated Press