{mosimage}Reuters - British Prime Minister Tony Blair warned Syria and Iran on Tuesday that they risked a confrontation if they continued to support terrorism and export instability to Iraq and elsewhere. By Adrian Croft

LOS ANGELES (Reuters) - British Prime Minister Tony Blair warned Syria and Iran on Tuesday that they risked a confrontation if they continued to support terrorism and export instability to Iraq and elsewhere.

In a speech urging a rethink of the West's strategy to defeat extremism in the Middle East, Blair accused Iran and Syria of helping extreme factions in Iraq and backing militant groups in Lebanon and Palestine.

Blair said the international community should tell Syria and Iran that they should either play by the same rules as the rest of the world "or be confronted."

"Their support of terrorism, their deliberate export of instability, their desire to see wrecked the democratic prospect in Iraq, is utterly unjustifiable, dangerous and wrong.

"If they keep raising the stakes, they will find they have miscalculated," Blair said in a speech to the World Affairs Council, a nonprofit organization in Los Angeles.

Blair, who has been heavily criticized at home for siding with the United States over the war between Israel and Hizbollah guerrillas in Lebanon, was asked after his speech whether NATO should take the lead in providing a multinational force in Lebanon.

Blair said it was too early to be clear what was most helpful for the situation, adding that whatever force was deployed should be capable of ensuring that the Lebanese people "vote in a democracy without outside interference from Syria or anyone else and without inside interference from armed militias."

BATTLE OF VALUES

Blair said the West must win the battle of democratic values if it is to defeat global extremism. It also needed to work relentlessly "week in, week out" to resolve the conflict between Israel and the Palestinians.

"Unless we reappraise our strategy, unless we revitalize the broader global agenda on poverty, climate change, trade, and ... bend every sinew of our will to making peace between Israel and Palestine, we will not win," he said.

"And this is a battle we must win."

Blair said the war in the Middle East was in part a fight between "reactionary Islam and moderate mainstream Islam" and that Western intervention in Iraq and Afghanistan had turned into "existential battles for reactionary Islam."

"We posed a threat not to their activities simply: but to their values, to the roots of their existence."

His speech came as three British soldiers were killed in Afghanistan and one was killed in Basra in southern Iraq.

Blair said Al Qaeda, Syria and Iran felt threatened by the prospect of Afghanistan and Iraq becoming "tolerant democracies."

"So in Iraq, Syria allowed al Qaeda operatives to cross the border. Iran has supported extremist Shia there. The purpose of the terrorism in Iraq is absolutely simple: carnage, causing sectarian hatred, leading to civil war," he said.

Hizbollah was armed by Iran, which was also financing militant elements in Palestinian group Hamas, he said.

Syria supported Hizbollah and housed hard-line leaders of Hamas, he said.

Blair was wrapping up a five-day visit to the United States during which he held talks with President George W. Bush in Washington over the Middle East crisis.

(Additional reporting by Jill Serjeant in Los Angeles)