ROME (AFP) -- Italians began a day of mourning Tuesday, preparing to pay their final respects at a massive state funeral here to 19 Italians killed in a truck bombing in Iraq.

Hundreds of thousands of ordinary Italians filed reverently past tricolor-wrapped coffins on Monday as the bodies lay in state in a chapel at Rome's Victor Emmaneul monument.

"Rome has once again shown its big heartedness, holding in its extraordinary embrace the bodies of the fallen of Nasiriyah," commented Rome Mayor Watler Veltroni.

Italy was expected to come to a standstill as the funeral cortege makes its way through central Rome to the Basilica of St. Paul's Outside-the-Walls.

The deaths of the 12 Carabinieri officers, their five military colleagues and two civilians have shocked a country which remains divided over Italy's military involvement in Iraq. Nine Iraqis were also killed in the blast in Nasiriyah in southern Iraq.

"Italy is living through this very hard test and must choose the way to go in the future taking into account that there are very strong difference of opinion on Iraq," said Cardinal Camillo Ruini, the head of the Italian Episcopal Conference, the concelebrant of the funeral mass which was due to begin at 11:30 A.M. (1030 GMT).

The country's main labor unions called for a 10-minute work stoppage in homage to the victims during the funeral, to be aired live on national television.

Schoolchildren were asked to observe a minute's silence in the nation's classrooms at 11:30 A.M.