The head of Lebanese movement Hezbollah on Friday warned Israel against attacking Lebanon or Syria, saying "hundreds of thousands" of Arab and Muslim fighters would be ready to strike back.
"The Israeli enemy should know that if it launches an attack on Syria or Lebanon, it's unknown whether the fighting will stay just between Lebanon and Israel, or Syria and Israel," Hassan Nasrallah said.
"I'm not saying countries would intervene directly -- but it would open the door for hundreds of thousands of fighters from all around the Arab and Islamic world to participate in this fight -- from Iraq, Yemen, Iran, Afghanistan, Pakistan," he said.
Nasrallah made the remarks in a speech broadcast on television to mark Jerusalem (Quds) Day, an annual show of solidarity with the Palestinians.
The commemoration was first launched by Ayatollah Ruhollah Khomeini, the late revolutionary leader of Iran -- a main sponsor of Hezbollah and staunch rival of Israel.
Hezbollah fighters from Lebanon, and others from Iran, Iraq, Pakistan and Afghanistan, are battling alongside regime forces in Syria to defend the government of President Bashar al-Assad. The powerful Shiite movement and Israel have fought many battles including a devastating 34-day war in 2006 that killed 1,200 people in Lebanon, mainly civilians, and 160 Israelis, mostly soldiers.
Border skirmishes have broken out occasionally since then, and Nasrallah on Friday said any future confrontation would be "very costly for Israel". Tensions were rising this week along the frontier, with Israel accusing Hezbollah of expanding observation posts to conduct reconnaissance missions across the border. Israel's ambassador to the United Nations, Danny Danon, denounced the "dangerous provocation" and sent a letter of protest to the Security Council.
And the head of Israel's air force said it would have "unimaginable" military power at hand in any future conflict with Hezbollah. "What the air force was able to do quantitatively in the... Lebanon war over the course of 34 days we can do today in 48-60 hours," Major General Amir Eshel said on Wednesday. "This is potential power unimaginable in its scope, much different to what we have seen in the past and far greater than people estimate."