Protesters kicked, punched and fired projectiles at John Howard's car today after the prime minister, who has been supportive of Israel, emerged from a Liberal Party conference in Perth.

About 200 protesters, many waving Lebanese and Palestinian flags, clashed violently with police as Mr Howard left a Perth hotel after delivering a keynote address to the WA Liberals' state conference.

Mr Howard had used the speech to attack Hizbollah, which is fighting Israel in southern Lebanon.

"It's not some kind of inspirational liberation organisation, it's a terrorist organisation," he said.

Mr Howard said he wanted a ceasefire in the Middle East, but this could only occur with international co-operation to disarm guerrilla forces.

"It will not be an effective or a lasting ceasefire unless there is the insertion into Lebanon of a large international stabilisation force, in sufficient numbers to be effective, and large enough to ... bring about the complete disarming of Hizbollah," he said.

As the prime minister departed, the protesters surged towards his car, demanding an end to the war which has killed hundreds of civilians.

"We want peace," they chanted as they mobbed Mr Howard's vehicle.