Italy's environment minister faces a razor-edge vote over his handling of a garbage crisis in Naples, with members of the ruling center-left coalition backing opposition calls for his resignation.

The Senate, where Prime Minister Romano Prodi has only a two-seat majority, will vote tomorrow on a motion blaming minister Alfonso Pecoraro Scanio for the mountains of rubbish that have piled up in the streets of Italy's third biggest city.

Pecoraro Scanio, leader of the Green party and dubbed by media "Signor No" because of his often uncompromising stance, would not be forced, technically, to step down if the vote goes against him.