<p><br /> Thousands of angry protesters have taken to the streets of Athens over proposed austerity measures.<br /> </p><p><br /> Clashes broke out as anarchists threw petrol bombs at riot police, who used tear gas to control the crowds at the May Day rallies.<br /> </p><p><br /> Foreign Office officials are monitoring the situation in Greece, a popular destination for British holidaymakers.<br /> </p><p><br /> Visitors have been warned they face further disruption on Wednesday, when flights in and out of Greek airports will be cancelled during a 24-hour strike.<br /> </p><p><br /> The Greek government is set to announce more sweeping spending cuts through 2012 to win support for an international loan package worth 45 billion euros this year alone.<br /> </p><p><br /> Nikos Diamantopoulos, who was taking part in a rally organised by pro-Communist unions, said: "These measures are death. How people are going to live tomorrow, how they're going to survive, I do not understand."<br /> </p><p><br /> In the northern Greek city of Thessaloniki, where more than 5,000 people demonstrated, protesters briefly clashed with police and smashed a few shopfronts and cash machines.<br /> </p>
