JAKARTA (Reuters) - Indonesia has no way to prevent Muslim militants traveling from its shores to the Middle East or elsewhere to wage war against Israel, Foreign Minister Hassan Wirajuda said on Tuesday.

The self-styled head of the Jakarta-based ASEAN Muslim Youth Movement said last week that more than 200 militants had been sent on missions to attack Israel's interests and countries that support the Jewish state.

"We are a country with a system in which people are extremely free to travel overseas and no exit permit is required," Minister Wirajuda told reporters.

"Therefore we don't have a method to prevent people (from traveling) but we have issued a travel advisory... to remind our citizens that it is not safe to travel to Lebanon for any purpose," he said.

Suaib Didu, the head of the Muslim youth group, told Reuters that fighters had been trained to carry out suicide bombings to revenge Israel's military strikes on the Palestinian territories and Lebanon.

On Tuesday, a spokesman for a group led by firebrand Muslim cleric Abu Bakar Bashir, the Indonesian Mujahideen Council, said 500 volunteers were ready to be dispatched to Lebanon and Palestinian territory.

"We should not let anyone stand in the way of the intention by some Muslims to go to Lebanon and Palestine," Fauzan al Anshori told Metro TV.

Wirajuda said sending volunteers to fight Israeli troops would be a "reckless" move.

"There are many ways to carry out jihad (holy struggle). What's most urgently needed by the Lebanese is humanitarian assistance such as medicine and medical supplies," he said.

Wirajuda reiterated the government's call for an immediate ceasefire in the Middle East and an expanded United Nations presence in Lebanon.

"We are of the view that there's no need for the establishment of a multinational force. The existing UNIFIL (United Nations Interim Force in Lebanon) should be reinforced," he said.

Defence Minister Juwono Sudarsono said separately it would be irrational for Indonesians to travel to the conflict-torn region as fighters.

"It is enough if they can demonstrate here. No need to fight over there. Trust the government to play the fitting role for Indonesia through peacekeeping troops if the United Nations decide an Indonesian force can be dispatched there," he told reporters.

"But like what the foreign minister said, we cannot forbid people from going abroad with their passports but we advise them to play an effective role through rational ways."

Indonesia has no diplomatic relations with Israel and historically has been a staunch supporter of the Palestinians.