Collapsing walls at the ancient Roman city of Pompeii have raised fresh concerns about Italy's efforts to maintain one of the world's most treasured sites, preserved for 2,000 years but now crumbling from neglect.

On Monday, site officials said part of a wall had collapsed on one of Pompeii's major streets after weeks of heavy rains and wind. Plaster had also fallen off the wall of the ornately frescoed House of the Small Fountain.

A series of collapses in Pompeii over the last month led Italian media to dub it a "Black November" for the ancient city, which was preserved under ash from a volcanic eruption in 79 A.D. and rediscovered in the 18th century.

The European Union is trying to help. It launched a $140 million restoration project for the site in February but work has only partially begun as bids by companies for contracts are still being assessed, says a site official.

The declaration of a state of emergency five years ago failed to halt the deterioration, amid allegations that funds were being siphoned off by the mafia, and reports of mismanagement and looting. The collapse of the frescoed House of the Gladiators caused international outcry in 2010.

"This is an incomprehensible delay. If culture is to be a priority in Italy we must start with Pompeii, now decimated by continuous collapses caused mainly by a lack of routine maintenance," Italy's National Association of Archaeologists stated.

Embarrassing moment

The fresh collapses come at an embarrassing moment for the government which in October passed a decree to improve access to Italy's heritage sites in order to stimulate tourism - Pompeii was declared a World Heritage Site by UNESCO.

The law ordered the Pompeii restoration project to be sped up and for the person to lead the works to be named. Culture Minister Massimo Bray now says a person would be named within a week.

The EU's regional fund spent 7.7 million euro on restoration at Pompeii during 2000-2006, but today just five individual sites are open at any one time due to damage, compared to 64 in 1956. Yet with over 2 million tourists each year, Pompeii is one of Italy's top attractions.

Open gallery view The House of the Gladiators, which collapsed in 2010, causing an international wail. Credit: AP