Since the debt crisis flared in 2009, Greece has imposed a series of spending cuts to satisfy lenders and avert bankruptcy. The culture ministry's budget has been cut by 35 percent and it has axed 2,000 staffers, mostly workers on temporary contracts.

The budget cuts have hit museums and archaeological sites hard, forcing some to shorten visiting hours or shut down and prompting concern about the level of security at some of the most precious archaeological sites.

"Our cultural heritage is not for sale," said Despina Koutsoumba, the head of the Greek Archaeologists' Association. "We don't want markets to rule over our cultural heritage, our history and our democracy."

She and other Greek archaeologists called on art lovers to protest the cuts by holding up posters like "Defend Greece's cultural heritage" in front of Greek statues in museums abroad, and posting a picture of that on the Internet.

They hope the campaign will convince the government to shelve plans for public sector lay offs and further cuts in 2012, including a 20 percent cut in funding for museum security.

Although provincial sites have borne the brunt of the cutbacks, even major showcase projects like the two-year-old Acropolis Museum have been feeling the chill.

"We need everyone's help. We don't want our museums to become store rooms," said Koutsoumba, warning that other austerity-hit countries could soon find themselves in Greece's predicament.

"What happened here will happen to other countries too."

Culture and Tourism Minister Pavlos Yeroulanos has said the government is doing its best to protect Greece's heritage.

But archaeologists say the roughly 7,000 archaeologists, guards and civil servants are not enough to adequately care for the 20,000 historical monuments, sites and museums, that attract millions of tourists every year.

In January, three works of art, including one by Pablo Picasso and another by Dutch painter Piet Mondrian, were stolen from the National Gallery in Athens.

A month later, armed thieves looted a museum in Greece's Olympia, birthplace of the Olympic Games, stealing bronze and pottery artefacts. Yeroulanos offered to resign, but his resignation was not accepted.

"Today it's the National Gallery or the museum in Olympia, but tomorrow it will be the Louvre, the Colosseum and museums in Germany," Koutsoumba said. "We need a shield of protection."

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