Italy's ANSA news agency reports that up to 150 of the victims will be buried, with top government and Roman Catholic church leaders expected to join mourners at the open-air state funeral in the worst-hit town of L'Aquila.

The mass is to celebrated by L'Aquila Archbishop Giuseppe Molinari.

Civil protection authorities have raised the death toll from Monday's quake -- the country's worst in three decades -- to 287. While many of the tens of thousands of people forced to flee their homes are still living in tent camps.

There has also been public anger over alleged delays in the rescue effort and apparent poor quality construction which has been blamed for increasing the death toll. Prosecutors have opened an inquiry into building standards.

Meanwhile, on a tour of the disaster zone, Italian President Giorgio Napolitano blamed "widespread irresponsibility" for the collapse of many modern buildings in the quake.

The Italian government estimates total repair costs to reach up to three billion euros, while it has already approved a package of emergency financial measures, which will provide money to pay rent, and suspended gas and electricity bills for two months.